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Why mvnrepository.com or nexus does not follow a convention to have a latest version, for example: <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>latest</version> </dependency> The version latest will always point to the latest version in the repository so instead of updating the pom.xml file, during the build, it will pick the latest on. Provided the library is backward compatible. | In Maven, dependencies are usually set up like this: <dependency> <groupId>wonderful-inc</groupId> <artifactId>dream-library</artifactId> <version>1.2.3</version> </dependency> Now, if you are working with libraries that have frequent releases, constantly updating the <version> tag can be somewhat annoying. Is there any way to tell Maven to always use the latest available version (from the repository)? |
I can't figure out how to change this or what I clicked to cause it but the object completely disappears if it's not highlighted | I don't know why but now, when i go in material preview or rendered (in solid mode it works fine), my object is entirely gray, or invisible idk, because it has the same color of the background. I've been working for days on this project without having this issue, it suddenly showed up. I tried opening other old projects and suddenly they all do the same so i guess it is some blender program setting that applies for all the projects, but idk how it happened cuz i didn't change anything :/, anyone got any tips? |
I Have one static Ip such as 1233.22.33.44 and i have two Servers that have IP: Server 1: 192.168.1.1 Server 2: 192.168.1.2 Server 1 running Website on Port default 80, I can access Web on Server 1 through , and I want set up Web Server Running on Server 2, how can i do that? Thanks for Reply! PS: Sorry for my English. | The situation may be resolved by my intention to purchase an IPv6 prefix for the VPS, but in the mean time I'd quite like to know if this is possible. Basically what I want to achieve is a simple interface to Node.JS apps running on the VPS via domain names, so that for instance I could have "steak.chaos-kitten.com" pointing to one node.js app and "lister.chaos-kitten.com" pointing to another, and perhaps "chaos-kitten.com" itself pointing to a third. I know you can't use DNS to point to a specific port, but is there some software solution I can employ that will redirect incoming GET requests to the appropriate node.js app based on the domain name? |
My question is, what if I want to charge my iphone that uses 5volts via USB, however what if I had a powersupply that could deliver 5volts upto 10amps, if I used this to charge my phone would it ruin the phone? I thought that the phone only draws what it needs from the powersupply to charge it. Or would I be best to buy a charger to be used to charge my phone? Are phone chargers smart and turn off when phone is charged? | Power supplies are available in a wide range of voltage and current ratings. If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify? What if I don't know the device's specs, but am replacing a previous power supply with particular ratings? Is it OK to go lower voltage, or should it always be higher? What about current? I don't want a 10 A supply to damage my 1 A device. |
So, when hovering over links, or anything else on the chromium window, the mouse cursor will not change, it will remain the last one that changed because of some click event. How to fix it? I am on ubuntu linux , I am using latest chromium 53.0.2785.143-0ubuntu0.14.04.1.1145 I have an NVidia GeForce GTS 250 | I'm currently running Ubuntu 14.04 LTS (not in a VirtualBox) with Chrome, and I have a interesting issue. Currently there is a solution to a similar problem listed and , but my problem is just slightly different and none of the known fixes for the other problem are working. My problem is that the mouse does not change when placed over things such as links where the mouse should turn into a pointing hand, or over text where there should be the I beam. Also, hover states and active states on website elements aren't being triggered either. However, if I'm currently scrolling or the mouse is held down, then everything works fine, but not while only moving the mouse. I have tried: Purge and reinstall of Chrome Running Chrome with --touch-devices=123 Trying to recreate this error on another system (Without success) Trying Opera (since it's also WebKit, which has the same issue) NOTE: The other more widely seen bug has symptoms that aren't affecting me. For example, my scrolling and text selection is working completely fine. Chrome Version 42.0.2311.90 (64-bit) UA Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.90 Safari/537.36 FirePHP/4Chrome |
Obviously something is wrong with this, but where is the error and why is it one? $$ \begin{align} \sqrt{-1} &= (-1)^{1/2} \\ &= (-1)^{2/4} \\ &= \sqrt[4]{(-1)^2} \\ &= \sqrt[4]{1} \\ &= 1. \end{align} $$ | I know there must be something unmathematical in the following but I don't know where it is: \begin{align} \sqrt{-1} &= i \\\\\ \frac1{\sqrt{-1}} &= \frac1i \\\\ \frac{\sqrt1}{\sqrt{-1}} &= \frac1i \\\\ \sqrt{\frac1{-1}} &= \frac1i \\\\ \sqrt{\frac{-1}1} &= \frac1i \\\\ \sqrt{-1} &= \frac1i \\\\ i &= \frac1i \\\\ i^2 &= 1 \\\\ -1 &= 1 \quad !!? \end{align} |
As I said in another post, I'm a new Ubuntu user. I've installed Ubuntu and I did not delete windows 7 , but after installing Ubuntu, windows was in boot menu but when I clicked on windows to load,I see this error: A disk read error occured press ctrl+Alt+ Del to restart I'm using Ubuntu right now, but I can't switch to windows .. I don't know what to do in order to have Ubuntu and windows simultaneously .. | I'm new to linux world. Just downloaded ubuntu and installed it alongside with windows 7 . In grub when I choose ubuntu, it opens with no problem, but when I try to open windows 7, this message appears: A Disk Read Error Occured. Press CTRL+ALT+DEL to restart. I googled for that problem which directed me to download a boot repair tool, when I choose : advanced options / retore MBR --> apply, then restart computer , It boot to win 7 without loading the grub menu. then I opened the live ubuntu from a USB, launched the "boot repair" again, choose : recommended repair , then restart, It returns to the first problem , grub menu appear, from which I can choose only ubuntu , but win 7 show this msg again : A Disk Read Error Occured. Press CTRL+ALT+DEL to restart. I repeated more and more with the same results ... What should I do? I created a boot info summary using the "boot repair tool" if this can help , it's in . |
I want to insert a special character "like 1350-28-1¼" FVL" in MySQL using insert query in PHP. I tried with real_escape_string() but it inserts "1350-28-1¼" FVL" in table. I also tried with htmlentities() but it inserts "1350-28-1 & frac14; & quot; FVL" in table. How do I insert this type of special character in a MySQL database table using PHP? | I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1. Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur? This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2. |
Earlier I used to toggle between tabs by swiping left or right and clicking on the tab I wanted to open. But know if I click on the change tabs icon, I can only see the list like this attached image. How to get back to toggling tabs? | I recently updated my Chrome for Android (currently on v68) and noticed that tapping on the box icon (next to address bar) gives a tab list instead of SystemUI type overview that Chrome used to give. See the two images below for comparison. I know that I can get that same view by swiping downwards from the address bar but I'm habitual of getting it from that box icon. So what can I do to get back that view from that box without reverting to a previous version of Chrome and without switching to an another browser (unless it is Chrome based)? |
I have an AWS server running Windows 2016 Datacenter. From the past few days, Windows Defender has been reporting Trojan:PHP/Obfuse.AR!MSR pointing to random phpXXXX.tmp files inside C:\Windows\Temp folder. I checked there are many files of that type in the temp folder but only 2-3 are reported by Windows Defender as infected. I tried opening these files (after downloading to local PC) in notepad and found they have some HTML & PHP code, primarily a form with file input. I tried searching for this on Google and some articles suggested that these are hack attempts. The only reason I have PHP enabled on Windows Server is because we need to run a WordPress site. The CPU and RAM usage on server has also increased over the last 10-15 days. It used to stay below 10% but now it varies between 30-40% with Windows Defender being the highest contributor. Is this bad? What steps should I take to investigate further and secure the server? Any directions would be helpful. Unfortunately, we cannot afford to engage a professional to look into this matter. | This is a about Server Security - Responding to Breach Events (Hacking) See Also: Canonical Version I suspect that one or more of my servers is compromised by a hacker, virus, or other mechanism: What are my first steps? When I arrive on site should I disconnect the server, preserve "evidence", are there other initial considerations? How do I go about getting services back online? How do I prevent the same thing from happening immediately again? Are there best practices or methodologies for learning from this incident? If I wanted to put a Incident Response Plan together, where would I start? Should this be part of my Disaster Recovery or Business Continuity Planning? Original Version 2011.01.02 - I'm on my way into work at 9.30 p.m. on a Sunday because our server has been compromised somehow and was resulting in a attack on our provider. The servers access to the Internet has been shut down which means over 5-600 of our clients sites are now down. Now this could be an FTP hack, or some weakness in code somewhere. I'm not sure till I get there. How can I track this down quickly? We're in for a whole lot of litigation if I don't get the server back up ASAP. Any help is appreciated. We are running Open SUSE 11.0. 2011.01.03 - Thanks to everyone for your help. Luckily I WASN'T the only person responsible for this server, just the nearest. We managed to resolve this problem, although it may not apply to many others in a different situation. I'll detail what we did. We unplugged the server from the net. It was performing (attempting to perform) a Denial Of Service attack on another server in Indonesia, and the guilty party was also based there. We firstly tried to identify where on the server this was coming from, considering we have over 500 sites on the server, we expected to be moonlighting for some time. However, with SSH access still, we ran a command to find all files edited or created in the time the attacks started. Luckily, the offending file was created over the winter holidays which meant that not many other files were created on the server at that time. We were then able to identify the offending file which was inside the uploaded images folder within a website. After a short cigarette break we concluded that, due to the files location, it must have been uploaded via a file upload facility that was inadequetly secured. After some googling, we found that there was a security vulnerability that allowed files to be uploaded, within the ZenCart admin panel, for a picture for a record company. (The section that it never really even used), posting this form just uploaded any file, it did not check the extension of the file, and didn't even check to see if the user was logged in. This meant that any files could be uploaded, including a PHP file for the attack. We secured the vulnerability with ZenCart on the infected site, and removed the offending files. The job was done, and I was home for 2 a.m. The Moral - Always apply security patches for ZenCart, or any other CMS system for that matter. As when security updates are released, the whole world is made aware of the vulnerability. - Always do backups, and backup your backups. - Employ or arrange for someone that will be there in times like these. To prevent anyone from relying on a panicy post on Server Fault. |
I have a few pairs of stereo air photos and I want to extract a DEM from them. I think that is possible using PCI (OrthoEngine), but I would like to do it using Open Source (or at least free) software. I've looking in GRASS GIS and Orfeo Toolbox but I didn't find how to do it? (It is possible that I have not looked correctly...). Is it possible? | Does ArcGIS Desktop or any of its native extensions allow me to create DEMs from stereo pairs (acquired by satellite, )? If the answer is a clear no, brownie points will go to an answer that proposes a viable alternative using OpenSource. |
Given the following module operation: $$8x + 51\pmod{10}$$ Details: $x \equiv y \pmod{m}$ is by definition equivalent to $m|(x−y)$. $x \equiv y \pmod{m}$ , $x,y\in \mathbb{Z}, m \in \mathbb{Z^+}$ iff $a \pmod {m} = b \pmod{m}$. Question 1: Can we split it as follows based on module details above: $$8x + 51\pmod{10} = 8$$ $$51\pmod{10} = 1$$ Then, $$8x + 1\pmod{10} = 8$$ Question 2: Is it possible to subtract numbers from the module operation $1$ from both sides: $$8x \pmod{10} = 7$$ Question 3: Suppose we have the quantity $8x \pmod{10} = 7$, then what is the meaning that the inverse of $8 \pmod{10}$ is $7 \pmod{10}$? Given the inverse, how we can multiply both sides by it as follows as this was not covered in basic module operations in $$7\cdot 8x \pmod{10} = 7 \cdot 7 \pmod{10}$$ We can conclude that $$56x \pmod{10} = 7 $$ | Suppose,I have a number 1256. I want (1256 % 11)! That is 2 . But, here, if i try in this way, ( (125 % 11 ) * 10 + 6 ) % 11 = 2. That is exactly the same answer 2 as above. I am confused , how This two process gives the similar answer ??? Even if , I try this method for any number n,m to find (n mod m) . How this works ?? Can anybody explain ? |
I read a book in the early 80's (sometime between 81 and 83) that I have been trying to remember the title of for a long time. I got the book from my high school librarian as a reading suggestion, so it may have been a young adult book, but I don't know. The only think I remember about the story is one of the weapons that the "good guys" wore. The weapon was a hand gun type of weapon that they wore in a holster that was on the forearm of their gun hand. The weapon was somehow connected to the nerves in their wrist so that when they tensed their hand or arm in a certain way the gun jumped into their hand. | I listened to this on audiobook and it was great. The premise was a human ends up travelling to an alien planet. The aliens have a perimeter to their 'base' that is under constant attack from the planet's animals. It is revealed towards the end that there is some sort of signal being transmitted that is making all the animals and plant life attack a certain point on the planet (where the aliens are). Other major plot points I remember: The human traveller falls in love with an alien. The aliens have a sort of virtual training environment that simulates life outside the perimeter, where plants attack you etc. There is a secondary alien group that the human ends up with, and although they are rivals to other group, they have a trade set up. Any help much appreciated! Thanks. |
The human race is on the run from alien attack and have established a colony world with only medieval level technology so the aliens can't find them by radio frequency transmissions, etc. There is one man in suspended animation in a satellite as a store of knowledge for the future. The medieval humans are at war so the satellite guy wakes up and intervenes in an Iron Man-style suit. The book was the first in a trilogy I think and published maybe late '90s. That's all I can remember but any help greatly appreciated | Between 2005-2008, I entered a Barnes and Noble and came across a book in the New Releases section that I regretted not purchasing. I remember only the following from the back-panel summary of the book: Humanity was more or less wiped out. The remains of humanity were put into a deep sleep on one (or more) large spaceship(s). When they arrived a new planet, they had a society where religion was/wasn't outlawed (can't remember anymore). A lot of bad stuff went down after humanity rebuilt itself on this new planet. |
I have URL like https://some-domain/auth/authenticate?auth=1c4cf948-0867-488d-8596&client_id=account&tab_id=0p-SoVza1Sw I want to get the value of tab_id by using regex. I have done it through JS but I want a regEx to return 0p-SoVza1Sw. I tried this /tab_id=([^&]+)&*/g but it matches with tab word also I know it would be easy but am not good at regex, Thank you | I want to match a portion of a string using a and then access that parenthesized substring: var myString = "something format_abc"; // I want "abc" var arr = /(?:^|\s)format_(.*?)(?:\s|$)/.exec(myString); console.log(arr); // Prints: [" format_abc", "abc"] .. so far so good. console.log(arr[1]); // Prints: undefined (???) console.log(arr[0]); // Prints: format_undefined (!!!) What am I doing wrong? I've discovered that there was nothing wrong with the regular expression code above: the actual string which I was testing against was this: "date format_%A" Reporting that "%A" is undefined seems a very strange behaviour, but it is not directly related to this question, so I've opened a new one, . The issue was that console.log takes its parameters like a printf statement, and since the string I was logging ("%A") had a special value, it was trying to find the value of the next parameter. |
Find all continuous real valued function such that $$(f(x))^2+C=\int\limits_0^xf(t)dt$$ for some $C\in\mathbb{R}$ If I set $F(x)=\int\limits_0^xf(t)dt$ then $F$ is differentiable and $F'(x)=f(x)$, so $(f(x))^2+C$ is diferentible as it does $\sqrt{F(x)-C}=|f(x)|$, and then $F'(x)=(|f(x)|^2+C)'=2|f(x)||f(x)|'=f(x)$. and then I don't know how to continue. I just see the solution $f(x)=0$ whith $C=0$. | Find all continuous functions $f$ satisfying $$\int_0^xf=(f(x))^2+C$$ for some constant $C \neq 0$, assuming that $f$ has at most one $0$. I have a question about the solution to this problem. It says that Clearly $f^2$ is differentiable everywhere, its derivative at $x$ is $f(x)$ (I'm assuming that this is because the left hand side is differentiable, the right hand side must be differentiable as well). So $f$ is differentiable at $x$ whenever $f(x) \neq 0$, and $$f(x)=2f(x)f'(x),$$ so $f'(x) = \frac{1}{2}$ at such points. Thus, $f= \frac{1}{2}x+b$ for some $b$ on any interval where it is non-zero; if $f$ has a zero, this gives two possible solutions, with two possible values of $b$, but since $f$ is assumed continuous, they must be the same. So we need $$\int_0^x(\frac{1}{2}t+b)dt=(\frac{1}{2}x+b)^2+C$$ so we must have $b=\sqrt{-C}$ or $-\sqrt{-C}$, leading to two solutions for $C \lt 0$. I don't understand the bolded statements. First, how does the differentiability of $f^2$ guarantee that $f$ is differentiable, and why only at $x$ where $f(x) \neq 0$? Next, why are there two possible solutions if $f$ has a zero, but since $f$ is continuous they must be the same? Finally, does the last statement mean that if $C \gt 0$, then there is no solution, since we're restricted to real numbers here? I would appreciate it if anyone answers my questions. |
:-) With the following preamble how can I reposition where the chapters start? Meaning each section is defined to start at almost the 2/3 of the page. There is a small space and then goes the "Section 1: blah blah". Can I start each section at the beginning of the page like the other pages? \documentclass[a4paper,12pt]{book} \setcounter{secnumdepth}{-2} \titleformat{\chapter}[display]{\normalfont\huge\bfseries}{}{20pt}{\Huge} \let\cleardoublepage\clearpage \usepackage[english,greek]{babel} \usepackage[utf8x]{inputenc} \usepackage{blindtext} \usepackage[pdftex]{graphicx} \usepackage[skip=2pt, font=small, labelformat = empty]{caption} \newcommand{\gr}{\selectlanguage{greek}} \newcommand{\en}{\selectlanguage{english}} \usepackage{wrapfig} \usepackage[paperwidth=17cm, paperheight=24cm]{geometry} \usepackage[onehalfspacing]{setspace} \usepackage{textcomp} \useshorthands{;} \defineshorthand{;}{?} \usepackage{fancyhdr} \fancyhf{} \fancyhead[LE]{\nouppercase{\leftmark}} \fancyhead[RO]{\nouppercase{\rightmark}} \fancyfoot[LE,RO]{\thepage} \pagestyle{fancy} \renewcommand{\chaptermark}[1]{ \markboth{#1}{} } \renewcommand{\sectionmark}[1]{ \markright{#1}{} } | How could I adjust the size and placement of chapter heading in my custom class? I am using report class as my base. When I used titlesec package inside my custom class, it threw error ! Package titlesec Error: Not allowed in `easy' settings. |
Can anyone tell me why I'm getting that extra title (picture's name .jpg at the top)? I don't want to include it. | I want to import graphics into my main input file using the macro \includegraphics. It does not work if the filename contains spaces. also discusses this subject, but there is no solution there. My compilation routine is latex->dvips->ps2pdf (because of PSTricks). |
I'm trying to analyze the outgoing requests of an application on my windows 10 computer, but I'm not aware of any way to capture the secret key needed to decrypt the traffic. I have used previously, but switched because of lack of protocol support. I know the key can be captured on chrome/firefox by setting the "SSLKEYLOGFILE" enviroment variable, but this is not relevant in this case, as the application in question does not support that type of logging. Therefore my question becomes: Is there a general method of capturing the secret key needed to decrypt SSL/TSL traffic in Wireshark, that can be applied regardless of application? Answer There is no general way of capturing the secret key needed to decrypt SSL/TSL messages, but one can use a proxy such as to achieve equivalent results in most cases, hence I found the "general method" I was looking for. | I'm trying to decrypt SSL traffic in Wireshark, and it partially works because I'm able to view the decrypted headers. The problem is that I don't see any of the packet contents, only their headers. Is there an explanation for this behaviour? A bit more detail: we used openssl to generate keys and certificates with the command: openssl req -config *.cnf -new -x509 -extensions v3_ca -keyout *.key -out *.crt -days 1825 and then to decrypt the private key to a PKCS#8 format, which wireshark supposedly supports, we issued this command: openssl pkcs8 -nocrypt -in *.key -informat DER -out *.key -outformat PEM In Wireshark we issued the following parameters in SSL decryption section: 10.10.10.10,443,http,*.key - where 10.10.10.10 is the client we're trying to MITM using sslsniff. We have also tried localhost and servers IP with no success. Any suggestions? |
I need get all the words of a UITextView of individual form. In an array for example. | What is the best way to tokenize/split a NSString in Objective-C? |
I want to set a record's value to NULL by just typing into the grid of the currently displayed table in MySQL Workbench and then pressing 'Apply', but when I try to do this, MySQL Workbench sets the value of the record to the string 'NULL'. Does anybody know how to do what I am trying to do? Obviously I could accomplish my objective by just typing the MySQL query, but this has happened to me a few times now while testing code and I figure there's an ever slightly easier way to do what I want. | I'm using the MySQL Query Browser (part of the ) and need to change a field to NULL, but I can't figure out how to do it - if I delete the value it tries to update it to ''. Typing "NULL" makes it try to update to 'NULL' (a string). I know I could just write a query to do it, but that defeats the entire purpose of the tool, no? |
Let $F$ be a field. Let $F[x]$ be the polynomial ring and $f(x)$ and $g(x)$ be 2 irreducible polynomials of same degree in $F[x]$. When do we have the 2 fields $$F[x]/<f(x)> \cong F[x]/<g(x)>$$ Well, I can think of $F[x]/<f(x)>$ as the field $F(\alpha)$ where $\alpha$ is the root of $f(x)$ and check if any algebraic combination of $\alpha$ with elements of $F$ is a root of $g(x)$. If it is then both the fields are the same/isomorphic. But is there any general condition on the 2 polynomials such that the isomorphism holds? | Let $K$ be a field and $f,g$ irreducible polynomials in $K[X]$, is there a nice iff condition for $K[X]/(f)\cong K[X]/(g)$? ($\cong$ denotes an isomorphism that is the identity on restriction to $K$). Thoughts: It is sufficient that they are $K^\times$ multiples of each other. I'd hoped this was necessary but it isn't as $\mathbb{Q}[X]/(X^2-2)\cong\mathbb{Q}(\sqrt2)=\mathbb{Q}(\sqrt2+1)\cong\mathbb{Q}[X]/(X^2-2X-1)$ with the middle two fields viewed as subfields of $\mathbb{C}$. It is necessary that they have the same degree. Please let me know if there are any other simple necessary conditions. Thanks! |
I am working on a python script, which requires reading values from a list in for loop and performing some operations on it. currently it looks like this: for i in someList: # do some operation here Now, this particular operation takes hours to complete, so what i want to be able to do is use multi-threading/sub-processes and process multiple items in parallel. So is there a way that I can run the for loop like: for i,j,k in someList: #do some operation here i know this syntax can be used to iterate over multiple lists simultaneously, but I want to be able to use multiple items of the same list. What i want from the loop is that the value of i,j and k update in the following manner: i = someList[1], j = someList[2], k = someList[3] in the next iteration: i = someList[4], j = someList[5], k = someList[6] | I have a Python script which takes as input a list of integers, which I need to work with four integers at a time. Unfortunately, I don't have control of the input, or I'd have it passed in as a list of four-element tuples. Currently, I'm iterating over it this way: for i in range(0, len(ints), 4): # dummy op for example code foo += ints[i] * ints[i + 1] + ints[i + 2] * ints[i + 3] It looks a lot like "C-think", though, which makes me suspect there's a more pythonic way of dealing with this situation. The list is discarded after iterating, so it needn't be preserved. Perhaps something like this would be better? while ints: foo += ints[0] * ints[1] + ints[2] * ints[3] ints[0:4] = [] Still doesn't quite "feel" right, though. :-/ Related question: |
Let $E$ be a separable Banach space and $(y_j)_{j\in \mathbb N}$ be a sequence in $B(0,1)$ which is dense in $B(0,1)$. Where $B(0,1)$ is the open ball of center $0$ and radius $1$. Show that the map \begin{align} A:~&l_1~~~~~~~~~\longrightarrow E\\ &(x_i)_{i\in\mathbb N}\longmapsto \sum_{i=1}^\infty x_iy_i \end{align} is linear, continuous, surjective. I don't have any idea to show the function $A$ is surjective. Can someone please help me. | Folland, "Real Analysis", Chapter 5.3, Exercise 36: Let $\mathcal{X}$ be a separable Banach space and let $\mu$ be counting measure on $\mathbf{N}$. Suppose that $\left\{x_n\right\}_1^\infty$ is a countable dense subset of the unit ball of $\mathcal{X}$, and define $T \colon L^1(\mu) \to \mathcal{X}$ by $Tf = \sum_1^\infty f(n) x_n$. (a) $T$ is bounded. (b) $T$ is surjective. I have proved (a). I would like help on (b). Here are my ideas so far. Say we want to show $y \in \mathcal{X}$ is in the image of $T$. Reduce to the case $||y|| = 1$ and let $x_{n_m} \to y$. My thought is to produce for each $N$ a function $f_N \in L^1(\mu)$ such that $||y - \sum_n^\infty f(n)x_n|| < 1/N$ and also such that the $f_N$ converge in $L^1(\mu)$ to some $f \in L^1(\mu)$. Then use the continuity of $T$ to conclude $T(f) = y$. The way I have been setting up my inequalities is as follows. Pick $M_N$ such that for all $m > M_N$, $||y - x_{n_m}|| < 1/N$. Then I want to define $f_N$ so that $$\sum_n^\infty f_N(n) = \sum_{m > M_N}^\infty f_N(m) = 1, $$ hence $$||y - T(f_N)|| = ||\sum_{m > M_N}^\infty f_N(m) y + \sum_n^\infty f_N(n)x_n|| \leq \sum_{m > M_N}^\infty f_N(m) || y - x_{n_m} || < \frac{1}{N}. $$ Presumably, if the $f_N$ are appropriately chosen, then I can find a dominating function and apply the Dominated Convergence Theorem to finish up. However, getting all these hypotheses to hold simultaneously has been difficult. In essence, the difficulty seems to be in requiring that the $f_N$ be "normalized" as well as possess a dominating function. If this method is feasible, at least it seems to require a bit of analysis to show the desired series all converge. Perhaps I am missing something cleaner. If so, a simpler solution would be much appreciated. -Thanks. |
I have a problem with the graininess that appears in the shade. I want to render an object with a nice and clean shadow. The result is a png with a transparent background. Render in Cycles engine. I have enabled Shadow Catcher, Transition, RGBA, Denoising - OpenImageDenoise . The number of Samples is 1000. Can I fix this problem somehow? | I am facing some issues with the shadow-catcher and denoiser in Blender 2.79. Denoising doesn't seem to have any effect on shadow catcher shadow. If I turn off shadow catcher on ground plane the desnoising works well. But if it's turned on - the shadow stays noisy. Also the shadow become much darker with shadow catcher turned on. Am I doing something wrong? How do I get noise free contact shadow and lighter shadow like the left render? Here is the .blend file of the scene in case someone wants to inspect it: Will really appreciate any help. |
I just bought a Nokia 6.1 phone. On the whole I like it, but today this popped up: The app is called "NPS" ("Net Promoter Score"?) version 9.0010.50. I found a discussion of it , but the only way mentioned to disable it doesn't work (my "User Experience Program/Diagnostic Report" option is already off). I don't like my time being wasted, but I like even less the idea that the phone is "phoning home" to yet another company. Any suggestions for how to disable or get rid of this app? (I'm tempted to respond as negatively as possible to every question the app poses...) | I'm using a Samsung I9000 and I have some annoying apps that came pre installed by the phone vendor, like a music store, a custom web browser and other memory leaking apps. Those crappy apps can't be uninstalled neither by Manage applications tool, nor by editing the apps tiles in the front menu. I guess I have to be a root user or something to get rid of those apps, but I don't know how. |
Looking for a flight from Chicago to Scotland in the summer, and the cheapest by far is to fly Toronto-Edinburgh. Outbound flight is direct while return flight connects through Chicago. I want to get off in Chicago. (This flight + one way Chicago to Toronto is still several hundred cheaper than Chicago-Edinburgh round trip) Wouldn't I have to pick up my baggage after customs inspection upon return to the US at O'Hare before boarding the connection to Toronto, so I could just leave the airport at that point? It's the last leg of my trip so having a leg canceled wouldn't be an issue. To add detail as to why this question is different than others -- I am specifically asking about baggage policy, since bags will be checked in this case. I recall a past flight back into the US with a domestic connection and I had to pick up my bags then drop them off with a connection agent to route to my final destination. Is this still policy? The caveat is that I am talking about a flight covering three countries total (Scotland -- US -- Canada) but wish to bypass the US to Canada leg. | Say I want to book a flight from Fort Lauderdale to Chicago. Say the airline also flies to St. Louis from Fort Launderdale but has a connecting flight through Chicago. If I book that flights from FLL->ORD->STL and just get off in Chicago, what possible problems can I run into, assuming I didn't check any bags and only have carry on? This scenario exist for Southwest, but I wanted this be more of a general question that would apply to all airlines. |
I have a 2017 Macbook Air 2017. A week ago I turned it on and wrote my password, then it shut down. I tried to turn on but nothing happened. I read some posts on the Internet and tried the following: Unplug the MagSafe 2. Open my MacBook Air. Disconnect the battery. Plug in the MagSafe 2. Reset the SMC (pressing Left Shift, Option, Control and Power for ten seconds and releasing at the same time). Connect the battery. Press power and Voila, It Turn On! I was using my Macbook very happy but now when I shut down my MacBook to go to sleep, the next day when I try to turn it on, nothing happened. It stay shut down like at the beginning and I have to repeat the steps to turn it on. Whats is the problem with my MacBook? What do you recommend me to do? Any idea how can I fix it? | I was just using my laptop normally when suddenly the whole computer just shut down. I turned it back on straight away and it was fine. Another hour passed and it did the same thing. I could also turn it on again. And then it happened again, this time I couldn't turn it back on!! I have never spilt any liquid over my laptop so it isn't liquid damage. I have tried resetting SMC, replugging the battery cable inside the computer, leaving the charger disconnected from the mac for a few hours, nothing works! The strange thing is when I have my charger disconnected and I press the little button on the side to show power, nothing happens. But when I do the same with the charger connected it shows full battery. I have a MacBook Pro 15" Early 2011 running OSX El Capitan. |
I have recently installed solaris 11, but I am an absolute beginner in unix systems. The only unix like environment I have got myself into before is ubuntu which was quite a bit different from solaris in my opinion. The main problem I am facing at the moment is that the NTFS windows HD partitions are not appearing in solaris file system, which was not the case when I used ubuntu. Every single file on my HD was exposed to me when I was in ubuntu. I have already tried to find the solution in the internet. Tried to solve it with the help of But had no success. The download links given for both FSWpart and FSWfsmisc is not working(giving a 404). I installed something called ntfs -g drive but I think I am not using it correctly as most of the time I am copying and pasting commands because I do not have sufficient knowledge to write them myself. Please any assistance in this matter is greatly appreciated. Thanks in advance. | Not sure if I have come to the right place with the right problem but I don't really have much option as I have not found even a close solution to my problems in any other website during my tireless search times in the internet. So, here it goes------- I have recently installed solaris 11. The main problem I am facing at the moment is that the NTFS windows HD partitions are not appearing in solaris file system, which was not the case when I used ubuntu. Every single file on my HD was exposed to me when I was in ubuntu. I installed something called ntfs -g drive but I think I am not using it correctly as most of the time I am copying and pasting commands because I do not have sufficient knowledge to write them myself. Any assistance in this matter? ** Yeah I am talking about the exact same ntfs -3g. But how can I see the windows HD partitions in solaris? |
I am trying to give some depth to my svg files. I have imported an svg file and then joined the curves together by grouping them. The extruding it self does not give any problems, however when i try to give it a bevel or adjust the offset these weird spikes stick out my object. Also, even though I joined the objects together i still can't extrude them all together. Am I doing the grouping wrong? | I exported an svg 1.1 file from Adobe Illustrator CS6. I joined all the shapes by pressing Ctrl+J. I set the curve shape to 2D. Then I extruded using the right hand side panel: So far so good. But when I try to apply even a slight bevel, all hell breaks loose: It does get less insane if I bring the bevel down by multiple factors of 10... But then I really don't have much of a bevel. Am I doing something wrong? Am I using the wrong kind of object? Should I be doing this with meshes? Do my curves just need cleaning up? |
typedef struct{ int tournamentNo; char tournamentName[61]; char toutnamentDate[15]; char tournamentCity[21]; }Tournament; printf(" : %d ", sizeof(Tournament)); result: 104 actual: 61+15+21 + 4 = 101 typedef struct{ int tournamentNo; char tournamentName[20]; char toutnamentDate[15]; char tournamentCity[21]; }Tournament; printf(" : %d ", sizeof(Tournament)); result: 60 actual: 20 + 15 +21 +4 = 60 Why different this ? | Why does the sizeof operator return a size larger for a structure than the total sizes of the structure's members? |
(Sorry for the weird title, but I can't figure out what actually the problem is) The following code should get a String from the command line first (which works), then the input is being splitted (works perfectly, too; I checked by printing both Strings before the if/else as you can see in the part I commented out again) and then it should check what the first part of the splitted String is. And for example if it equals "tweet" it should procedure with the Tweet method. But somehow it doesn't get that right. It always executes the else statement... Scanner sc = new Scanner(System.in); System.out.print("> "); String input = sc.nextLine(); String[] splitString = input.split(" "); if(splitString.length != 2){ throw new IllegalArgumentException(); } String command = splitString[0]; String value = splitString[1]; /*System.out.print(command); System.out.print(value);*/ if(command == "tweet") { Tweet(value); } else if(command == "help") { ShowHelp(); } else { System.out.println("Command "+command+" not found."); } I tried entering "tweet asdf", but it returns > tweet asdf Command tweet not found. What did I do wrong? I'm confused D: | I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug. Is == bad? When should it and should it not be used? What's the difference? |
I am trying to cut a long video into several small pieces. Any recommended tools can do the task? | What video editing software would you recommend on Ubuntu (or Linux in general) and why? It can be for either beginners or experienced users. Please only place one piece of software per response and include details to what makes it great! |
When navigating from chat, the Writers Stack Exchange seems to be assigned the World Building Stack Exchange icon. I am using Firefox 57.0 on Ubuntu. The error was duplicatable upon revisit. | Self descript. I know it's already been asked and . But apparently it's still an issue. This only started happening to me this week that I've noticed. Per the comments in the linked answer, a hard refresh should fix it but alas, it does not. Firefox 57.0. Works on SE but doesn't work on SO or many of the other sites I visit. I disabled my add-ons and did a hard refresh but still to no avail. I've exited my browser cleared my temp stuffs as well. |
I am trying to remove the duplicates in a list my_list In [13]: my_list Out[13]: [[(-7.7725138974675732, -79.168560840024711), (-7.7725138974675732, -79.168560840024711), (-5.5, -59.0), (-4.4, -48.3), (-3.2, -37.5), (-2.1, -26.9), (-0.9, -16.2), (2.7974572775821454, 4.4251549647685868), (2.7974572775821454, 4.4251549647685868)], [(2.7974572775821454, 4.4251549647685868), (2.7974572775821454, 4.4251549647685868), (29.8, 16.4), (41.8, 16.9), (53.1, 17.2), (74.767340748230566, 15.947522750252775), (74.767340748230566, 15.947522750252775), (74.767340748230566, 15.947522750252775), (97.8, 13.4), (109.2, 14.9), (125.57323627494615, 19.53393479479609)], [(68.773124224303274, -79.616585806160444), (68.773124224303274, -79.616585806160444), (71.141449110088374, -58.675607868692225), (73.874255065554237, -27.94398092967819), (73.874255065554237, -27.94398092967819), (73.874255065554237, -27.94398092967819), (74.5, -2.9), (74.767340748230566, 15.947522750252775)], [(-109.09700131981562, -32.09602243732722), (-108.3, -32.7), (-81.9, -52.7), (-64.94343179027949, -62.943395681375023), (-64.94343179027949, -62.943395681375023), (-44.8, -70.5), (-32.2, -74.1), (-7.7725138974675732, -79.168560840024711), (-7.7725138974675732, -79.168560840024711), (10.6, -80.1), (21.6, -80.4), (32.8, -80.6), (43.9, -80.6), (68.773124224303274, -79.616585806160444), (68.773124224303274, -79.616585806160444), (68.773124224303274, -79.616585806160444), (94.59403067734813, -75.99089907199837)], [(-57.743037814594651, 0.48281269760971313), (-57.743037814594651, 0.48281269760971313), (-61.5, -30.9), (-62.9, -42.2), (-64.94343179027949, -62.943395681375023), (-64.94343179027949, -62.943395681375023)], [(73.874255065554237, -27.94398092967819), (73.874255065554237, -27.94398092967819), (113.3911596081064, -33.232674908171724)], [(71.141449110088374, -58.675607868692225), (71.141449110088374, -58.675607868692225)], [(2.7974572775821454, 4.4251549647685868), (-17.6, 3.5), (-57.743037814594651, 0.48281269760971313), (-57.743037814594651, 0.48281269760971313)]] Then, I do my_list = list(set(my_list)) In [20]: my_list Out[20]: [[(-7.7725138974675732, -79.168560840024711), (-3.2, -37.5), (-2.1, -26.9), (-5.5, -59.0), (-4.4, -48.3), (-0.9, -16.2), (2.7974572775821454, 4.4251549647685868)], [(109.2, 14.9), (41.8, 16.9), (97.8, 13.4), (29.8, 16.4), (53.1, 17.2), (125.57323627494615, 19.53393479479609), (74.767340748230566, 15.947522750252775), (2.7974572775821454, 4.4251549647685868)], [(73.874255065554237, -27.94398092967819), (74.5, -2.9), (74.767340748230566, 15.947522750252775), (68.773124224303274, -79.616585806160444), (71.141449110088374, -58.675607868692225)], [(-108.3, -32.7), (-7.7725138974675732, -79.168560840024711), (-44.8, -70.5), (-81.9, -52.7), (10.6, -80.1), (-64.94343179027949, -62.943395681375023), (94.59403067734813, -75.99089907199837), (-109.09700131981562, -32.09602243732722), (68.773124224303274, -79.616585806160444), (32.8, -80.6), (-32.2, -74.1), (21.6, -80.4), (43.9, -80.6)], [(-62.9, -42.2), (-64.94343179027949, -62.943395681375023), (-57.743037814594651, 0.48281269760971313), (-61.5, -30.9)], [(73.874255065554237, -27.94398092967819), (113.3911596081064, -33.232674908171724)], [(71.141449110088374, -58.675607868692225)], [(-17.6, 3.5), (-57.743037814594651, 0.48281269760971313), (2.7974572775821454, 4.4251549647685868)]] As can be seen, the order of the data has changed. The order is important for me. So I have to maintain the order after the operation. Why is it so and how do I maintain the order? | Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this: def uniq(input): output = [] for x in input: if x not in output: output.append(x) return output (Thanks to for that .) But I'd like to avail myself of a built-in or a more Pythonic idiom if possible. Related question: |
I have project that I worked on in blender 2.6/2.7x and now Im decided to switch to blender 2.9 but when I open that file I'v got some groups which are gread out and dont see them i view port. How can I make them visable again ? | The selection toggle arrows in the Outliner disappeared. Is there some preference in the settings that has to be turned on? |
If I am raging, can I enter the rage again, without dropping out of the rage, to reset the minute duration? RAW preferred. RAI accepted. | Is there anything preventing a Barbarian that is currently raging from using a bonus action to expend another rage and restart the 1 minute duration on their rage? |
prove that if $k|m$, then $\mathbb{Z}_m$ has a subgroup of order $k$. im not sure where to start with this. any help is appreciated. thanks! | Prove that if $k\mid m$, then $Z_m$ has a subgroup of order $k.$ Ok, so this doesn't look like too hard of a problem. So do I just show that it is closed under multiplication and inverse? I just don't know how I would do that with a problem like this. Can anyone help me get started please? |
This assignment is asking for getLuminance to "return the luminance of a Pixel as the average of the three color channel values" and I think i have it set up right, but for some reason in the line while ( sunflower.hasNext() ) { 'hasNext' is giving an error that says "Dereferencing possible null pointer" I have no idea what is going on. the line n = (int) TARGET/getLuminance(p); is also giving an error that is requiring a Picture and a Pixel, but getLuminance only requires a pixel so I'm not sure what's happening there as well. public Luminance() { Picture sunflower; // picture to be modified sunflower = new Picture(); display = new PictureDisplayer(sunflower); display.waitForUser(); setLuminance(sunflower, 127.5); display.close(); System.exit(0); } private int getLuminance (Pixel p) { Picture sunflower = null; int r; // red value of pixel int g; // green value of pixel int b; // blue value of pixel int v = 0; // average while ( sunflower.hasNext() ) { p = sunflower.next(); r = p.getRed(); g = p.getGreen(); b = p.getBlue(); v = (r + g + b)/3; clip (v); } return v; } private int clip(int val){ if (val <=255){ return val; } else { return 255; } } private void setLuminance(Picture sunflower, double TARGET) { Pixel p; int r; // red value of pixel int g; // green value of pixel int b; // blue value of pixel int n; //getLuminance(sunflower); while ( sunflower.hasNext() ) { p = sunflower.next(); r = p.getRed(); g = p.getGreen(); b = p.getBlue(); n = (int) TARGET/getLuminance(p); p.setRed(n*r); p.setGreen(n*g); p.setBlue(n*b); } } /** * @param args the command line arguments */ public static void main(String[] args) {Luminance r = new Luminance(); // TODO code application logic here } | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
Let $\mathcal{M}$ be our message space and $\mathcal{K}$ our key space. Now, let $\mathrm{E} : \mathcal{K} \times \mathcal{M} \to \mathcal{M}$ be a block cipher. Define the block cipher $\mathrm{EX}((k_1, k_2, k_3), m) := k_1 \oplus \mathrm{E}(k_2, m \oplus k_3)$, where $m \in \mathcal{M}$, $k_2 \in \mathcal{K}$, and $k_1$ and $k_3$ are of the same length as the message (I suppose I could write $k_1, k_3 \in \mathcal{M}$). In the case of DES, we get , giving us a total key size of $64 + 56 + 64 = 184$ bits. At the end of (as well as what can be inferred from the Wikipedia entry), prof. Dan Boneh mentions that there is a simple attack on all block ciphers of the form $\mathrm{EX}$ in time $|\mathcal{K}| \cdot |\mathcal{M}|$, meaning a simple attack on DESX in time $2^{120}$. I finished the course during this summer and generally had no problems, but could not figure this attack out for DESX / the general case. Can anyone explain to me what it is? | The passage said that the computational load to attack DES-X can be reduced to approximately $2^{(56+64)}=2^{120}$ steps,and the storage of data sets should be $2^{64}$. But I can't figure why it is time complexity $2^{120}$ and the (space complexity) of data sets should be $2^{64}$. Can somebody help? |
Whats the best way to use multiple LDRs to power up an LED? Currently I’m using one LDR which turns on an LED when it senses light. But now I want to use three LDRs (at different locations) to trigger the same LED. The LED should turn on when any of the three LDRs sense light. Thanks in advance! | I wnat to use 8 IR sensors (4 on front of vest, 2 on back and 2 on headband like lazertag vest) that when each of sensors hitted by IR, turn on a led. I don't want to use any microcontroller so a simple circuit is what I want. I can achieve this by one IR reciever but I want to use 8 sensor. Help me please. |
I'm making something for my friends and I've been trying to find a summon item generator with a custom name and I have found one but the custom name does not work. /summon item -137 28 -204 {Item:{id:black_terracotta,Count:1,tag:{display:{Name:"Dark Matter"}}}} | How can I give myself an item with a custom name, and how can I search for a player holding an item with a certain name. This is what I tried: /give @p minecraft:acacia_button{display:{Name:"ieat",Lore:[ieat]}} 1 It only gave me a regular acacia button. |
First attempt at install returned errors related to HDD. I wiped the drive using DBAN planning to replace the HDD. When attempting Ubuntu install after HDD wipe I received the following errors: [ 0.000000] [Firmware Bug]: TSC_DEADLINE disabled due to Errata: plesae update microcode to version: 0x20 (or later) [ 0.32000] [mce: [Hardware Error]: CPU 0: Machine Check: 0 Bank 6: ae00000040110a [ 0.32000] [mce: [Hardware Error]: TSC 0 ABBR ffb07640 MISC 38a0000006 [ 0.32000] [mce: [Hardware Error]: PROCESSOR 0:40651 TIME 1537996692 SOCKET 0 APIC 0 microcode 17 0 Need to know if I have more than HDD issues here before replacing HDD | I saw several bugs and error messages when I was looking by chance into the tool called "logs". Being a newbie in Ubuntu I have no idea how to deal with these bugs, where to report them or how to fix them. Any help to guide me here? The bug I have (which is listed under important) reads: [Firmware Bug]: TSC_DEADLINE disabled due to Errata; please update microcode to version: 0x52 (or later) |
Here's a good Halloween mystery for you. On Tuesday morning I saw a spooky apparition...the vague, spectral shape of 15 rep points off in the distance in a dark corner, that vanished before my eyes as I approached to get a closer look--without leaving a trace! Despite its rapid dissolution into nothingness, I managed to snap a picture of it, and I'm hoping some paranormal investigator (or maybe a mod) can explain how it is that I have a picture proving that it was not my imagination, despite the total lack of physical evidence. Here's the ghost story: When I first looked at SO on Tuedsday morning, I saw the this banner at the top of a previously open tab: My rep had been at 2,580 just before I went to bed the night before, so naturally I figured an answer must have been accepted. However, the very next SO page I looked at (I don't recall what, just some other page) showed that the rep was back down to 2,580. I figured there must have been an accept/unaccept. I took a look at my profile to find out which answer so I could see if it required further attention. To my utter befuddlement, the profile not only showed no record of an accept/unaccept, it showed no reputation changes at all for the day: I'm on Eastern Standard Time, so when I went to bed with the rep at 2,580, it was already about 6 hours into this zero-change day (which in fact remains at zero, with no indication of any changes at all). After reading "", I checked out , but it shed no light on this eerie enigma: BTW, in case anyone jumps to assume that any question having to do with lost rep is a complaint or a lament, I want to be clear: This isn't "hey, no fair, I want my rep back, boo-hoo!" I don't necessarily know that there was ever any reason for the rep to have gone up in the first place, since it appeared as mysteriously as it disappeared, and no clues were left behind. But I'm the curious sort and I like to understand how things work, especially if I see something that seems out of whack. If I were a cat I'd be dead. (Unless I had black fur, in which case this would be my big night.) So, what happened? It it possible for someone to accept/unaccept fast enough that it doesn't leave any record? And if so, why would I see the rep change in the banner? Or did I just see the ghost of an accepted answer long deceased that rose from the dead to practice haunting in preparation for tonight? | When I visit the reputation tab of my profile, I see a lot of stuff. I can make out some of it, but not all. What do all the event types mean? Why do some events show an odd reputation gain or not show any reputation change at all? Why are some events sometimes highlighted in yellow? My reputation suddenly dropped, but I don't see anything. What happened? Why do some events disappear from my reputation history? |
I have an issue with an API that requires me to run a BASE64 and MD5 of a string. While a JAVASCRIPT code I created works well with this API, I need it in PHP, and I get the worng answer. While testing the issue, I came to a conclusion that the issue is with the way the base64_encode function works in PHP, differs, and that creates the problem. I am attaching a code that will demostrate it var CryptoJS = require("crypto-js"); var testStr = 'hello world!'; console.log(String(CryptoJS.SHA256(testStr))); # outputs 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9 console.log(CryptoJS.enc.Base64.stringify( CryptoJS.SHA256(testStr) )); # outputs dQnlvaDHYtK6x/kNdYtbImP6Acy8VCq1498WO+CObKk= <?php $testStr = 'hello world!'; echo hash('sha256', $testStr); # outputs 7509e5bda0c762d2bac7f90d758b5b2263fa01ccbc542ab5e3df163be08e6ca9 echo '<br />'; echo base64_encode(hash('sha256', $testStr)); # outputs NzUwOWU1YmRhMGM3NjJkMmJhYzdmOTBkNzU4YjViMjI2M2ZhMDFjY2JjNTQyYWI1ZTNkZjE2M2JlMDhlNmNhOQ== I need the PHP code to output the same BASE64 result as the JS code. Can you please clarify what I'm doing wrong, and how can I fix it? | I have a PHP script that can encode a PNG image to a Base64 string. I'd like to do the same thing using JavaScript. I know how to open files, but I'm not sure how to do the encoding. I'm not used to working with binary data. |
Let $\mathbb{Z}[\frac{{1+\sqrt{-3}}}{2}]$ be the ring of integers where $\alpha=\frac{{1+\sqrt{-3}}}{2}$. I wish to show that $1-\alpha$ is a prime and check whether 3 is a prime or not. To show that $1-\alpha$ is prime, suppose $1-\alpha$ divides $(a+b\alpha)(c+d\alpha)$. Then I wish to show that it divides one of them. I wrote down the division algorithm for $1-\alpha$ divides $(a+b\alpha)(c+d\alpha)$ but it's a big mess that I can't seem to make sense of. Any help is appreciated. | $\mathbb{Z}[\omega] = \{a + b\omega : a, b\text{ are integers}\}$ $\omega = e^{2πi/3} = -\frac12 + \frac{\sqrt3}2i$ My task is to factor the numbers $2, 3, 4, 5, 6, 7, 8, 9, 10, 11$ into irreducibles in $\mathbb{Z}[\omega]$. I don't know if I'm overthinking this, but I do not even know where to start. I'm used to doing this in $\mathbb{Z}[i]$ and $\mathbb{Z}[\sqrt2]$, but I have no idea how to approach $\mathbb{Z}[\omega]$. EDIT: I am not supposed to use the norm in this exercise. My biggest struggle right now is just figuring out how to factor these numbers. Using guess and check I was able to find: $$3 = (2 + \omega)(1 - \omega)$$ $$7 = (3 + \omega)(2 - \omega)$$ I'm plugging and chugging into Wolfram Alpha right now. Is there any better way to do this? |
How far and how clear could the "Eye of Sauron" see? Could it see through the whole of Middle-earth or is it limited to only Mordor? Could it distinguish the human face, the small artifacts like rings, or not? Saruman says the "Eye of Sauron" "sees all — his gaze pierces cloud, shadow, earth and flesh. You know of what I speak, Gandalf — a great Eye… lidless… wreathed in flame" when he is intimidating Gandalf. This implies that Sauron could see everything, just like Superman. If this is true, how could the One Ring escape his gaze? Sauron just needed to scan the land of the Shire. I am afraid that the meeting in Rivendell is also under Sauron's sight. When Frodo brings up the One Ring and Gimli wields his axe, Sauron will see. And once he saw the Ring, he can see it always. Does this mean that Saruman is exaggerating? What is the true limit of the "Eye of Sauron"? | I am aware that the "Eye of Sauron" in Peter Jackson's movies was not Sauron's actual physical form. What the answers at '' don't indicate is, despite this, what abilities of vision Sauron may have had. Did he have the ability to see from afar? If so, what are his limitations or details of this power? Is it some kind of Elvish-sight like Legolas but stronger? Was it a magical power? Or perhaps with the help of the Palantir (I'm not sure of this last one because I dont remember if the Palantir could only see what other Palantíri were seeing or anything he wanted)? |
I am trying to work on an application to read SA citizenship ID on Android Studio but when I run the application it is not even opening? The Source Code : package com.example.magicidapplication; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; public class MainActivity extends AppCompatActivity { EditText etID; Button btnSubmit; TextView tvResults; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); etID = findViewById(R.id.etID); btnSubmit = findViewById(R.id.btnSubmit); tvResults = findViewById(R.id.tvResults); tvResults.setVisibility(View.GONE); btnSubmit.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { String idNumber = etID.getText().toString().trim(); String dob =idNumber.substring(0,6); int gender = Integer.parseInt(Character.toString(idNumber.charAt(6))); String sGender; if(gender<5) sGender = getString(R.string.female); else sGender = getString(R.string.male); int nationality = Integer.parseInt(Character.toString(idNumber.charAt(10))); String sNationality; if(nationality == 0) sNationality = getString(R.string.sacit); else sNationality = getString(R.string.permanentresident); String text = getString(R.string.dob) + dob + getString(R.string.newline) + getString(R.string.gender) + sGender + getString(R.string.newline) + getString(R.string.nationality) + sNationality; tvResults.setText(text); tvResults.setVisibility(View.VISIBLE); } }); } } Error : 2019-03-09 17:34:40.900 5053-5053/com.example.magicidapplication E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.magicidapplication, PID: 5053 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.magicidapplication/com.example.magicidapplication.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setVisibility(int)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) at android.app.ActivityThread.-wrap11(Unknown Source:0) I got error like this what to do. | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
From I get most of the following example references. With the third entry @article generated by Mendeley. %File mb-bibtex.tex, then \jobname = mb-bibtex \RequirePackage{filecontents} % loading package filecontents % writing file \jobname.bib, for example mb-bibtex.bib. \begin{filecontents*}{\jobname.bib} @Book{companion, author = {Goossens, Michel and Mittelbach, Frank and Samarin, Alexander}, title = {The LaTeX Companion}, edition = {1}, publisher = {Addison-Wesley}, location = {Reading, Mass.}, year = {1994} } @Book{adams, title = {The Restaurant at the End of the Universe}, author = {Douglas Adams}, series = {The Hitchhiker's Guide to the Galaxy}, publisher = {Pan Macmillan}, year = {1980} } @article{KESSLER2003d, author = {KESSLER, BRETT}, doi = {10.1080/02702710390227228}, file = {:Z$\backslash$:/Mendeley Literature/KESSLER/Reading Psychology/KESSLER - 2003 - Is English Spelling Chaotic Misconceptions Concerning Its Irregularity.pdf:pdf}, issn = {0270-2711}, journal = {Reading Psychology}, number = {3-4}, pages = {267--289}, title = {{Is English Spelling Chaotic? Misconceptions Concerning Its Irregularity}}, url = {http://www.tandfonline.com/doi/abs/10.1080/02702710390227228}, volume = {24}, year = {2003} } \end{filecontents*} \documentclass{article} \usepackage[numbers]{natbib} % bibliography style \usepackage[colorlinks]{hyperref} % better urls in bibliography \begin{document} Test of bibliography: The \LaTeX{} companion~\cite{companion}, the funny book of Adams~\cite{adams}. **The other citations work, but the Mendeley reference ~\cite{KESSLER2003d} does not. Perhaps it is a feature of the number of attributes generated?** \bibliographystyle{plainnat} % needs package natbib \bibliography{\jobname} % uses \jobname.bib, according to \jobname.tex \end{document} The first two show up as [2], the funny book of Adams [1] but the third shows up as [? ] at least on my system. Thanks for any help you can provide. | I am trying to use bibtex for the first time. I am on windows 7, using TeXstudio. I am trying to follow the steps of . I have created a .bib file, put it in the right directory and written the code in my .tex file. However, I do not know how to compile bibtex with TeXstudio (I looked around in the menus but didn't find it). Most tutorials I found don't explain how to do it, or say to run a command, which I'm not sure how to do. Any help much appreciated! |
Suppose $X \subseteq \mathbb{R}$ is well-ordered by $<$, the normal ordering on $\mathbb{R}$. Is it then countable? If so, how to prove this. I've tried to set up a bijection as follows: $$ \phi : \mathbb{N} \to X : n \mapsto \ <\textrm{-least element of } X \backslash \phi(\mathbb{N} \upharpoonright n) $$ I.e, $0$ maps to the least element of $X$, 1 maps to the least element of $X \backslash \{x_1\}$, $2$ maps to the least element of $X \backslash \{x_1,x_2\}$ etc. This is injective by construction, but I'm not sure if it is surjective. | I know that the usual ordering of $\mathbb R$ is not a well-ordering but is there an uncountable $S\subset \mathbb R$ such that S is well-ordered by $<_\mathbb R$? Intuitively I'd say there is no such set but intuitively I'd also say there is no well-ordered uncountable set at all, which is obviously wrong. I still struggle to grasp the idea of an uncountable, well-ordered set. |
Using my sandisk cruzer glide (8GB), I was putting windows 7 onto the usb to install onto another PC. When halfway through, it said "This drive is read-only". I got confused, but then I went to computer and the I couldn't even open the drive. I checked it in diskmgmt.msc and it said "read only". Afterwards I checked the USB on gparted live and it turns out the partiton has changed to HFS+. After trying to rewrite the partition table (and it failing because of read-only) I tried using diskpart next apparently I just had to do attributes disk clear readonly (with disk being the USB) but that did nothing. When doing attributes disk it still said Current read-only state: Yes even though below it says Read Only: No. I've also tried chipgenius, and only got this far: Device Name: ++USB Mass Storage Device(SanDisk Cruzer Blade USB Device) PnP Device ID: VID = 0781 PID = 5567 Serial Number: 2005485881119AF2F91A Revision: 1.20 Device Type: Standard USB device - Chip Vendor: (No match record) Chip Part-Number: (No match record) Product Vendor: SanDisk Product Model: Cruzer Blade Tools on Web: (N/A) What should I do now? I am completely out of ideas. (I have also tried BOOTICE, but that did nothing too) | When I plug in my USB flash drive, it shows up on my computer as write-protected or read-only. I am unable to transfer data to it, nor can I modify or delete any files already stored on it. I also cannot repartition or reformat the drive using Windows Disk Management, DiskPart, GParted, or other tools. The drive does not have a write-protect switch. Why did this happen and what can I do about it? Is there a way to remove the write protection? (Note that this can happen with some memory cards, too, as they often use controllers similar to those used in flash drives. In some cases, the system may report that the drive or card was formatted successfully even though it was never actually formatted; the original data reappears when the device is reinserted.) This question comes up often and the answers are usually the same. This post is meant to provide a definitive, canonical answer for this problem. Feel free to edit the answer to add additional details. |
I have a 1TB big file (disk-image from a damaged drive) and a 1.3MB small file (beginning of a disk-file). Using the contents of the small file, I want to overwrite portions of the big file. That is, I want to insert/overwrite the first 1.3MB of the 1TB-image using the small file. Using small temporary files for testing I was unable to overwrite parts of the files. Rather, dd overwrote the files completely. This is not what I want. Is dd able to do this? | I have an empty file (only zeroes are in it) of size 9,0KB and I need to write another file (with size 1,1KB) to it, but the first file must not lose its size or the rest of its contents. So if the whole file is 00000000000000... now, I need to write second file in it and leave the zeroes as they are. I have tried to use dd, but I haven't succeed - file resizes. dd if=out/one.img of=out/go.img Does anybody know how can I do it? |
I always remove files from my machine using sudo rm -rf file, and today I found that shred does a better job in terms of preventing files from being recovered later. My question is: I have an SSD only in my machine, and I'd like to know if removing files using shred instead of rm will decrease the lifespan of my SSD a lot, or since it's just a file it does not matter that much. Disclaimer: I know that flash disks are not bullet-proof when using shred, I read in many places that it's impossible to guarantee 100% that the files will not be recoverable, but I'm not hiding files from gov etc, just want to delete them for good in case I sell my computer in the future. I keep shred's default 3 overwrite passes. | When trying to securely wipe SSDs, we have several problems: SSDs wear out after a limited amount of erase cycles SSDs have a controller that dynamically maps LBAs (logical block addresses used by the system to access the disk) to NVRAM cells (the actual flash memory cells) to balance the wear, which means telling the disk to overwrite the blocks that formerly stored a specific file may result in overwriting any other spare blocks. SSDs have a notable percentage of reserve capacity that is used to compensate dying storage cells and reduce wearing. They are not visible to the system and might hold old data fragments. Now what options do we have from inside Ubuntu to securely wipe SSDs? I've heard that some newer SSDs should be able to securely wipe themselves, but how do I find out whether my SSD is capable of this and how would I trigger it? There should also be an ATA secure erase command, how do I find out if that is supported and how would I trigger that? Are there also ways to securely wipe only a given file or only unused space? I guess making a backup of all partitions, securely wiping the entire disk and then restoring the backup would be possible but sounds too complicated and would take too long to be practical. Are there other alternatives? If not, what tools can I use to backup partitions without also backing up already deleted files? Of course the standard tools like shred or wipe are not usable here for the points described above. They simply overwrite a a file (by overwriting its file system clusters which are bound to LBAs which are not constantly pointing on the same flash cells due to the wear levelling controller). |
If I have x = (0, 1, 2, 3, 4), and I want to get all the elements other the first two, but in reverse order, why is it supposed to be x[:1:-1] or x[:-4:-1] rather than x[2::-1]? | I need a good explanation (references are a plus) on Python's slice notation. To me, this notation needs a bit of picking up. It looks extremely powerful, but I haven't quite got my head around it. |
Can I say "I told you he is going to the book club" when he has already gone there by now; or is it necessary to back-shift it to past i.e. "I told you he was going to the book club". So will I be understood perfectly if I used the "is going" version (not back=shifting it). This situation seems new to me. So I thought I'd ask that: Does it seem difficult to understand for the other person if we do not back-shift to past??. And is it gramaticaly correct?? | I know the past tense carries the past tense in every dependent clause, but referring specifically to places or to things that are eternal, like the Earth, seems a bit weird and therefore we sometimes (I believe incorrectly) say He didn't know that New Jersey was actually on the East Coast. Because it still is. Or He thought the Earth was round. So is it square now? Logically speaking, would you consider the use of past tense here a bit confusing in a day-to-day speech in these examples? Would you instinctively opt for using the present tense? |
I am using Gammu for receiving SMS. Once received I am sending them as emails. Yet if sender ID of the SMS contains space, my script is unable to process a file. I.e.: If the file name is IN20210409_104439_00_SOME NAME_00.txt runonreceive script uses $1 to handle the filename but it saves only IN20210409_104439_00_SOME and obviously such file doesn't exist which brings errors. runonreceive script: sed -i '1 i\Subject: Incoming sms\n\n' /var/spool/gammu/inbox/$1 cat /var/spool/gammu/inbox/$1 | msmtp desrired@email.com So I am looking for a solution for handling full filename (with spaces) or to rename the file in that script (on-the-fly) and send out renamed SMS as email. | Or, an introductory guide to robust filename handling and other string passing in shell scripts. I wrote a shell script which works well most of the time. But it chokes on some inputs (e.g. on some file names). I encountered a problem such as the following: I have a file name containing a space hello world, and it was treated as two separate files hello and world. I have an input line with two consecutive spaces and they shrank to one in the input. Leading and trailing whitespace disappears from input lines. Sometimes, when the input contains one of the characters \[*?, they are replaced by some text which is is actually the name of files. There is an apostrophe ' (or a double quote ") in the input and things got weird after that point. There is a backslash in the input (or: I am using Cygwin and some of my file names have Windows-style \ separators). What is going on and how do I fix it? |
As the title says I have to show that for $R$ a commutative ring with neutral element, $ R/ I=\{x+I\mid x\in R\}$ is a ring if $I$ is an ideal and it isn't if $I$ is only a subring. It's the first time I am hearing about Rings so it's not that easy for me. I am proving the Ring conditions and the first one is that it has to be an abelian group. Let's start with the associative property: We take $x,y,z \in R/I$: We have to show that $(x+I+y+I)+z+I=x+I+(y+I+z+I)$ For example on the left hand side I guess that I have to do $((x+y)+I)+z+I$ and then $(x+y+z)+I$ and same with the other side but what gives me the right to write $(x+I+y+I)=((x+y)+I)$, why can I take $x$ and $y$ together and then the same logic with $z$ and also (this might be very trivial) why is the $I$ only counted once and not 3 times. And also, what does the Ideal give me in this specific case that the subring does not? Thanks in advance for the help. | From Wikipedia: Given a ring R and a two-sided ideal I in R, we may define an equivalence relation ~ on R as follows: a ~ b if and only if a − b is in I. Using the ideal properties, it is not difficult to check that ~ is a congruence relation. In case a ~ b, we say that a and b are congruent modulo I. The equivalence class of the element a in R is given by [a] = a + I := { a + r : r in I }. This equivalence class is also sometimes written as a mod I and called the "residue class of a modulo I". The set of all such equivalence classes is denoted by R/I; it becomes a ring, the factor ring or quotient ring of R modulo I, if one defines (a + I) + (b + I) = (a + b) + I; (a + I)(b + I) = (a b) + I. Suppose that we no longer restrict $I$ to be an ideal, but just any set that is a subset of $R$ and is not an ideal of $R$. Then would it be impossible to satisfy (a + I) + (b + I) = (a + b) + I and (a + I)(b + I) = (a b) + I all the time if $I$ is not an ideal? |
Limit selection to visible is on! This is driving me bonkers. I hit a button somewhere and now my mesh is like this in edit mode: Note: it's fine in object mode. Please help! :-( edit: i meant limit selection to visible IS on lol | I have recently started using blender and one of the models I'm working on has dark shadows along edges. I started this model from scratch. I can't remember them being there when I first started the model, but I had trouble joining areas together and think I've pressed something I shouldn't have. However, there are so many options I'm not sure what I did. Here is an image of what I mean The one on the left has the shadow. As a test I started a new model, which is on the right in the image, and as you can see it doesn't have any shadows. Also, occluded vertices partially show through the model. Occlusion doesn't work properly. In orthogonal view small darkened triangles appear along the the edges. I don't really want to start the model again from scratch so any ideas on how to remove this shadow would be great. Thanks. |
int main() { Pair<int, int> A = makePair (10, 20); cout << A ; return 0; } it give me error here (makePair is not define) and i define it in header file template<class T1, class T2> class Pair{ private: T1 first; T2 second; public: Pair(T1, T2); Pair() {}; Pair<T1, T2> makePair(T1 a, T2 b); void operator==(const Pair& other); friend ostream& operator<<(ostream& out, const Pair<T1, T2>& A); }; and this is another file called pair.cpp that i used a template classes in it template<class T1, class T2> Pair<T1, T2> makePair(T1 a, T2 b) { return (Pair<T1, T2>(a, b)); } | Quote from : The only portable way of using templates at the moment is to implement them in header files by using inline functions. Why is this? (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.) |
\documentclass[12pt,a4paper,oneside]{report} \usepackage[colon]{natbib} \begin{document} \citep{most2014a} \citep{most2014b} \bibliographystyle{agsm} \bibliography{ref} \end{document} this code will give me and the bibiliography to be Is there a way I can make the in-text citation to be (Mostaghimi et al., 2014a) and (Mostaghimi et al., 2014b)? The ref.bib includes, @article{most2014a, title={A control volume finite element method for adaptive mesh simulation of flow in heap leaching}, author={Mostaghimi, Peyman and Tollit, Brendan S and Neethling, Stephen J and Gorman, Gerard J and Pain, Christopher C}, journal={Journal of Engineering Mathematics}, volume={87}, number={1}, pages={111--121}, year={2014}, publisher={Springer} } @Article{most2014b, author = {Mostaghimi, Peyman and Ilankoon, I. M. Saman K. and Neethling, Stephen J.}, title = {{Use of mesh adaptivity in simulation of flow in packed beds - A case study}}, journal = {Minerals Engineering}, year = {2014}, volume = {63}, pages = {157--163}, issn = {08926875}, isbn = {0892-6875}, keywords = {Computational modelling,Control volume finite element methods,Mesh adaptivity,Multiphase flow,Packed beds}, publisher = {Elsevier Ltd}, } I want to use natbib/agsm (because I want to get the bibliography in the sttached style) and to make the uniquenames go away. But cannot find a way to do it. Appreciate if anyone can help. | With BibTeX and the harvard/AGSM style, some references (from authors who have multiple papers per year) aren't abbreviated to "et al.", with the addition of a, b, et cetera. For example, with the code attached below, I get: Only one paper is abbreviated to et al., the others not. Any idea why this is happening? The in-text references should be Basu et al. (2008a) and Basu et al. (2008b), which I believe AGSM should automatically do? \documentclass[10pt,a4paper]{article} \usepackage{natbib} \begin{document} \cite{basu2008a, basu2008b, beare2006} \bibliographystyle{agsm} \bibliography{references.bib} \end{document} With BibTeX file (references.bib): @string{jam="J. Appl. Meteor."} @string{ag="Acta Geop."} @string{blm="Bound.-Layer Meteor."} @article{basu2008a, author={Basu, S. and Vinuesa, J.-F. and Swift, A.}, title={Dynamic {LES} modeling of a diurnal cycle}, journal=jam, year={2008}, volume={47}, number={4}, pages={1156-1174} } @article{basu2008b, author={Basu, S. and Holtslag, A. A. M. and Wiel, B. J. H. and Moene, A. F. and Steeneveld, G. J.}, title={An inconvenient "truth" about using sensible heat flux as a surface boundary condition in models under stably stratified regimes}, year={2008}, journal=ag, volume={56}, number={1}, pages={88-99} } @ARTICLE{beare2006, author={Beare,R. J. and Macvean,M. K. and Holtslag,A. A. M. and Cuxart,J. and Esau,I. and Golaz,J. -. and Jimenez,M. A. and Khairoutdinov,M. and Kosovic,B. and Lewellen,D. and Lund,T. S. and Lundquist,J. K. and McCabe,A. and Moene,A. F. and Noh,Y. and Raasch,S. and Sullivan,P.}, title={An intercomparison of large-eddy simulations of the stable boundary layer}, journal=blm, year={2006}, volume={118}, number={2}, pages={247-272} } |
I'd like to be able to rotate my VIEW (not my model, not my camera either) around the Y-axis. This would allow me to select some vertices using a box selection. I fear it cannot be done, but I hope some one proves me wrong. My research so far is little promising: Q: How to rotate my view around the Y-axis? | How do I rotate the viewport around the local (to the view port) - Z axis? Basically what you would get if you were to hit R with the camera selected in camera view. |
I am DMing a new 4e group, and I am interested in approaching the game as a "theater of the mind" style combat rather than the traditional grid format. We are locked into doing D&D 4e because of the resources my players have available, but I believe they will be open to an approach that follows the spirit, rather than the letter, of the combat rules. What can I, as a DM, do to make theater of the mind combat engaging and reasonably consistent with the 4e rules set? I am open to suggestions and techniques from other systems as long as I can put them into a D&D game without breaking the core mechanic of dice roll + bonuses vs. check number. | A friend told me that he would like to try playing a gridless game next - still on tabletop, but without the gridlines. Is there any difference in the game except for movement? There are some things I don't know how to go about like line of sight, flanking, and traps and invisible enemies. Any help? |
I have read that the and spell combo can be annoying for DMs but I'm confused on why it works. In the description for the spell it states: The transformation lasts for the duration, or until the target drops to 0 hit points or dies. When it reverts to its normal form, the creature returns to the number of hit points it had before it transformed. If it reverts as a result of dropping to 0 hit points, any excess damage carries over to its normal form. When a polymorphed creature dies from power word kill, shouldn't it revert back to its normal form with its previous number of hit points? How does the power word kill spell affect a creature with polymorph cast on it (whose new form has less than 100 HP)? | Power Word Kill is a 9th level spell that "compel[s] a creature to die" as long as it has less than 100 hit points. If this is cast on a druid in wild-shape form with less than 100 HP, does the druid die or does he only revert to his normal state? Is the "creature" the druid himself? Is wild-shape a creature on top of the druid, or is he always the same creature? I realize that a druid is only knocked out of wild-shape if he hits 0 hit points or is knocked unconscious, so my personal take is that he would simply just die due to the wording of the spell, but I was curious if I was perhaps missing something. |
I've searched around; found the minimum processor requirements for Ubuntu 16.04 in an offical format. I can't find offical guidelines for 12.04 and 14.04 ... just various people giving their opinions. Does anyone know the URL(s) for where Ubuntu bury this information? - I have an old 32-bit machine with a T1350 processor (not even dual-core) running at 1.8GHz - It's running Windows 10 slowly with it's maximum 4gb of installed RAM. - I have Lubuntu downloaded ... - I'm just thinking that Ubuntu may give me a better experience than Lubuntu ... but which to choose ... Thanks folks. Regards, T | For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and such as: with a lighter desktop than the usual Gnome and Unity with the even lighter LXDE desktop Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements? |
ORIGINAL QUESTION (before the "possible duplicate" tag was added): Could someone please look at the last few comments under the main question at I can find no valid (posted) policy why I am not allowed to answer the question. If there is such an official policy as "the association bonus does not count" please post a link to it in response to this question. REVISED QUESTION (after the "possible duplicate" tag was added): Apparently this question has morphed quite a bit. As I detail in my own answer to this question below (I used an answer to include screengrab images) there is a discrepancy between the two different Stack Exchange sites. There is also a discrepancy between the official policy on reputation and this "does not count" tangent policy that is not mentioned in the official policy. Can someone please tell me why: (1) If "doesn't count" is official policy why is it not in the official policy page on reputation? (2) If this is official Stack Exchange-wide policy then why are there different messages on different sites, some mentioning "doesn't count" and other not? (3) If "doesn't count" is official policy why did it change? Our co-founder Jeff Atwood wrote an official description of the purpose of cross-site association bonus points: Nowhere in that description do I see an exception for protected questions. | I registered on only to post an answer to . However, since it's a protected question, I am not allowed to answer it. (I found this info from ). Worth to mention, I can comment on the above question, just not post an answer. I was under the impression that the whole point of association bonus was to bypass such limits, so why isn't that the case for answering protected questions? |
I'm not sure if there is any change in SO rules or I might be missing something. But one of my got accepted today & I get +10 points for it instead of +15. What is the cause of that ? How exactly 10 points are calculated here ? | On Stack Exchange, users may gain a certain level of reputation. What does reputation do? How can a user gain or lose reputation? See also in the Help Center - Maximum amount of votes a user can use in a day and reputation requirements to vote. - How to get an exact overview of the actions that got you your reputation. - A full list of all privileges granted at each reputation level on all sites. |
Using Retrofit2 to parse JSON in but getting NULL pointer exception & I don't know why? JSON response: { "query": { "count": 1, "created": "2016-04-29T17:19:45Z", "lang": "US", "results": { "quote": [{ "name": "Talon", "tix": "50.0000", "avg": "34757600", }] } } } Query class: public class Query { @SerializedName("query") private String query = null; } Results class: public class Results { @SerializedName("results") private String results = null; @SerializedName("results") private List<Quote> Quotes; public List<Quote> getQuotes() { return Quotes; } } Quote class: public class Quote { @SerializedName("name") private String Name; public String getName() { return Name; } @SerializedName("tix") private String Tix; public String getTix() { return Tix; } @SerializedName("avg") private String Avg; public String getAvg() { return Avg; } } Error returned in Android Studio logcat: java.lang.NullPointerException: storage == null at Activity.java:60. That line contains: data = new ArrayList<>(Arrays.asList(jsonResponse.getQuotes())); I'm not certain if the NULL is because the model classes aren't correct or something else & uncertain how/where to begin to fix it? I've looked at 4 other questions that have the same error but none were using Retrofit or JSON... | What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them? What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely? |
If we want to evaluate $$f(x)=\frac{e^x-1-x}{x^2}$$ then we have to observe its large relative error as $x\to 0$. My question is that how can we find a method so that we can compute $f(x)$ to full machine precision for all $|x|<1$? So far, I have been able to use a Taylor series to show that $$f(x)=\frac{1}{2!}+\frac{x}{3!}+\frac{x^2}{4!}+\ldots$$ And now I suspect that we have to find the remainder, right? How would I do this? | When evaluating $f(x)=\left(\dfrac{e^x-1-x}{x^2}\right)$, we observe large relative error as $x \rightarrow 0$. Find a method to evaluate $f(x)$ to full machine precision for all $|x|<1$. |
I see a lot of solutions to resolving the problem exemplified by Illegal instruction (core dumped) But, I'm wondering what exactly that means? What generates that error, and what's the root cause of it? Is that the CPU getting someone it believes is an instruction but can't decode? What happens under the hood to generate that error? From dmesg, I see [429572.598803] traps: test[4054] trap invalid opcode ip:400066 sp:ffac8cc0 error:0 in test[400000+1000] [429758.598292] traps: test[4401] trap invalid opcode ip:400066 sp:ffa3f990 error:0 in test[400000+1000] [430066.170626] traps: test[4854] trap invalid opcode ip:400066 sp:ff8ab000 error:0 in test[400000+1000] [430439.855002] traps: test[5212] trap invalid opcode ip:8048071 sp:ffce2fa0 error:0 in test[8048000+1000] | I sometimes get a little confused by all of the signals that a process can receive. As I understand it, a process has a default handler (signal disposition) for each of these signals, but it can provide its own handler by calling . So here is my question: what causes each of the signals to be sent? I realize that you can manually send signals to running processes via the -s parameter to kill, but what are the natural circumstances under which these signals are sent? For example, when does SIGINT get sent? Also, are there any restrictions on which signals can be handled? Can even SIGSEGV signals be processed and control returned to the application? |
\documentclass{beamer} \usepackage{graphics} \mode<presentation> { \usepackage{breqn} \usetheme{Frankfurt} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \begin{align*} \bar{v}\sim {|\Omega|\over 4\epsilon DN}\left[1+{\epsilon\over \pi}\log\left(\frac{2}{\epsilon}\right)+\frac{\epsilon}{\pi}\left(-\frac{9N}{5}+2(N-2)\log 2\\+\frac{3}{2}+\frac{4}{N}\mathcal{H}(x_1,\dots,x_N)\right)\right] \end{align*} Issue is \right is not working. I mean on right hand side bracket is closing. How do I resolve it. Thanks. | I have a very long equation that must be separated into two lines, and it has several pairs of nesting \left \right delimiters. Unfortunately, it seems that they need to be on the same line in order for them to work. Also I'm using the align environment because I need the aligning functionality. Is there a way to have the size of delimiters automatically adjusted over multiple lines? |
I have a 9th level fighter with Battle Master Archetype. Can I multiclass and take another level of Fighter but to advance in Champion this time as an Archetype? | The way that 5e works, each class has a sub class that dictates a heap of class features. The question here is generally, can a character of a specific class take levels in that same class in order to gain access to the low level features of another sub-class. The best example of this would either be the wizard or the cleric taking additional levels of wizard/cleric in order to gain access to another domain or school. Like can a Life cleric take levels of Storm cleric or similar? If this were allowed, what would the effects be on Maximum spell level and other class level based abilities? |
I have a valid Indian visa in the US for an expired passport. Additional I have a new US passport. Can I carry both my passports with me when I'm traveling to India? Will I have problems at the immigration at Bombay airport? | I recently had to renew my passport. The expired one has an Indian visa that will be valid until 2016. Is it necessary for me to get the visa transferred to the renewed passport, or can I get through customs in India (likely Mumbai) if I have both the expired and the renewed passports with me? |
I tried browsing and cant fnd the command for the double bracket symbol found below: | I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out? |
sometimes using rm -rf in script could be catastrophic example rm -rf $TMP/$folder when TMP and $folder are without any value , it will actually removing all under "/" so I am asking how to use the rm -rf in the scripts so it will be safe? | Sometimes I use, $PROJECT_HOME/* to delete all files in the project. When the environment variable, PROJECT_HOME is not set (because I did su and the new user doesn't have this environment variable set), it starts deleting all files from the root folder. This is apocalyptic. How can I configure bash to throw error, when I use an undefined environment variable in the shell? |
hi I have this code \begin{table}[h] \centering \caption{My caption} \label{my-label} \begin{tabular}{c|c|c|c|c|c|c|} \cline{2-7} & Windows Forms & PDF & Windows Forms/GDI+ & Windows Media Player & Direct3D & \textbf{WPF} \\ \hline \multicolumn{1}{|c|}{Grafické rozhranie} & X & & & & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{Dokumenty na obrazovke} & X & & & & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{Dokumenty s pevným,formátom} & & X & & & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{Obrázky} & & & X & & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{Video a zvuk} & & & & X & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{2D grafika} & & & X & & & \textbf{X} \\ \hline \multicolumn{1}{|c|}{3D grafika} & & & & & X & \textbf{X} \\ \hline \end{tabular} \end{table}` and I have this error File ended while scanning use of \@cline Can you help me pls? | I tried to use the Slovak language with the booktabs package. Let's see a couple of cases. slovak is included in the options to babel \usepackage[english,slovak]{babel} or \usepackage[slovak,english]{babel} or \usepackage[slovak]{babel}` "slovak" is NOT included in the options to babel \usepackage[english]{babel} Similarly two cases for \cmidrule A. \cmidrule{2-3} is included in the table B. \cmidrule{2-3} is NOT included in the table If both (slovak+\cmidrule) are included (case 1A), then following error occurrs Paragraph ended before \@@@cmidrule was complete (and a lot of other errors) In the other cases (1B, 2A and 2B) (NO slovak or NO \cmidrule), then pdflatex is succesful Does anybody know why 1A is wrong? And how to use slovak and \cmidrule together (case 1A)? \documentclass[10pt]{book} \usepackage[english,slovak]{babel} \usepackage{booktabs} \begin{document} \begin{tabular}{ccc} A & B & C \\ %\cmidrule{2-3} A & B & C \\ \end{tabular} \end{document} I have Win7, TeXstudio 2.5.2 |
I'm trying to check if a machine is a ThinkPad or not using something like this: sudo dmidecode | grep ThinkPad I want the end result return true or false (or 1/0). I'm thinking the solution might be something like this: sudo dmidecode | grep -c ThinkPad | test xargs -gt 0 But I'm not sure how to properly use xargs here. | As a part of this script, I need to be able to check if the first argument given matches the first word of file. If it does, exit with an error message; if it doesn't, append the arguments to the file. I understand how to write the if statement, but not how to use grep within a script. I understand that grep will look something like this grep ^$1 schemas.txt I feel like this should be much easier than I am making it. I'm getting an error "too many arguments" on the if statement. I got rid of the space between grep -q and then got an error binary operator expected. if [ grep -q ^$1 schemas.txt ] then echo "Schema already exists. Please try again" exit 1 else echo "$@" >> schemas.txt fi |
I have only recently started to learn quantum mechanics and I have only gone so far as to solve the hydrogen atom using Schrödinger's equation and the corresponding Hamiltonian, but all this has me wondering if it is possible to find a wave function for a planet-sun or moon-planet system. I know that this would be amazingly(and needlessly) more complicated than the classical solution. So is this possible, have people done it, and can we learn more from this approach? | Many introductory quantum mechanics textbooks include simple exercises on computing the de Broglie wavelength of macroscopic objects, often contrasting the results with that of a proton, etc. For instance, this example, taken from a textbook: Calculate the de Broglie wavelength for (a) a proton of kinetic energy 70 MeV (b) a 100 g bullet moving at 900 m/s The pedagogical motivation behind these questions is obvious: when the de Broglie wavelength is small compared to the size of an object, the wave behaviour of the object is undetectable. But what is the validity of the actual approach of applying the formula naively? Of course, a 100g bullet is not a fundamental object of 100g but a lattice of some $10^{23}$ atoms bound by the electromagnetic force. But is the naive answer close to the actual one (i.e. within an order of magnitude or two)? How does one even calculate the de Broglie wavelength for a many body system accurately? |
Why do the Klingons in ENT look different than the Klingons in TOS? I understand the explanation for the difference after TOS, but since ENT is before TOS. | Through the course of the Star Trek franchise, some species have undergone significant changes in their appearance. For example, here is a Klingon as seen in The Original Series. And, here is one from The Next Generation. Quite interestingly, if we go further back into Star Trek universe history, we find that Klingons from before the time of TOS looked much like they did in TNG. Here's one from Enterprise. Klingons weren't the only ones who went through this, and it didn't just happen in the transition from TOS to the TNG/DS9/VOY era. Here's a Trill from an episode in TNG. And, this is one from DS9. I'm sure these aren't the only species to have undergone changes like this. Have there ever been in-universe explanations for these, or others? |
Let's define equivalence relation on group $\mathbb{R}$ by setting $x\sim y$ iff $x-y\in\mathbb{Z}$ by all $x,y\in\mathbb{R}$. What is the quotient topology? For example if we set $x=\sqrt{2}$ and $y=\sqrt{2} + 2$, then $x-y\in\mathbb{Z}$. So this looks similar to the case where you replace $\mathbb{Z}$ with $\mathbb{Q}$, but $\mathbb{Z}$ is not dense in $\mathbb{R}$. In that case the quotient topology is indiscrete. Could someone please open up this a bit for me? | There is this example at the Wikipedia article on Quotient spaces (QS): Consider the set $X = \mathbb{R}$ of all real numbers with the ordinary topology, and write $x \sim y$ if and only if $x−y$ is an integer. Then the quotient space $X/\sim$ is homeomorphic to the unit circle $S^1$ via the homeomorphism which sends the equivalence class of $x$ to $\exp(2πix)$. I understand relations, equivalence relation and equivalence class but quotient space is still too abstract for me. This seems like a simple enough example to begin with. I understand (sort of) the definition but I can't visualize. And by this example and others, there is a lot of visualizing going on here! torus, circles etc. |
I have been trying to solve a problem and have given my answer in the form of a determinant, namely: \begin{align*} \det\begin{pmatrix} \binom{q}{2} & q & 1 & 0 & \dots & 0 \\ \binom{q}{3} & \binom{q}{2} & q & 1 & \dots & 0 \\ \binom{q}{4} & \binom{q}{3} & \binom{q}{2} & q & \dots & 0 \\ \binom{q}{5} & \binom{q}{4} & \binom{q}{3} & \binom{q}{2} & \dots & 0 \\ \vdots & \vdots & \vdots & \dots & \ddots & q \\ \binom{q}{n+1} & \binom{q}{n} & \binom{q}{n-1} & \binom{q}{n-2} & \dots & \binom{q}{2} \end{pmatrix} \end{align*} This is probably enough, but I thought I'd challange myself and dust off my old linear algebra skills. Unfortunately, it is not going well. I have attempted brute forcing it by multiplying out coefficients, but I don't think that is the way to go, because I am getting nowhere. Everytime I touch it I seem to be increasing the complexity rather than decreasing it... Is there a good way to tackle this problem, or is this as good as it gets? Any help would be much appreciated! | I trying to prove a statement, which boils down to showing that the determinant of a specific matrix is nonzero. I use the convention that $\binom{n}{k} = 0$ if $k > n$ or $k < 0$. Let $k,l$ be natural numbers such that $k \le l$. Then the $n\times n$-Matrix $A$ is defined to have the entries $a_{ij} = \binom{l}{k +i - j}$. So it looks like $A = \left( \begin{array}{cccccc} \binom{l}{k} & \cdots & \binom{l}{0} & 0 & \cdots & 0 \\ \vdots & \ddots & & \ddots & \ddots & \vdots \\ \binom{l}{l} & & \ddots & & \ddots & 0 \\ 0& \ddots && \ddots & & \binom{l}{0}\\ \vdots&\ddots&\ddots&&\ddots&\vdots\\ 0&\cdots&0& \binom{l}{l} & \cdots & \binom{l}{k} \end{array}\right)$. Clearly the cases $k = l$ and $k = 0$ are trivial, since $A$ is then triangular. My first idea was to use the formula $\binom{r}{s} = \binom{r-1}{s-1} + \binom{r}{s}$ and add columns/rows to each other. But that does not work out that well... So if anyone has any ideas, or this matrix is known to be invertible, I would be very thankful. |
I don't know if I'm just randomly blanking or if I never really knew and have just been going with the flow, but I'm not sure what x represents. In early high school they were degrees, eg. $\sin(30)$ which equaled $0.5$. Later on we learned about radians and $\pi$, and how $\sin {\pi \over 3}$ was equal to $\sqrt 3 \over 2$. Now I'm in Uni and I'm discovering that I maybe don't know trigonometry as well as I should. For example, when doing the squeeze theorem, and I'm asked to find the limit of $\sin(n) \over n$, what is the $n$? Is it in radians? degrees? It's for graphing so what should I visualize? $n$ as just a $x$ value to try and find any $y$?? | I was just wondering if you use degrees or radians in trig functions. For example if I have a degree of 0.5 would I do: Sin(0.5) or would I have to convert that to radians? Or does it not matter either way? |
I came up with the following glob for matching everything but . and ..: * .[!.]* ..?* Does this really do its job? | I was surprised recently when I did something like mv ./* ../somedirectory and found that files like .gitignore were not moved. I do most of my work in zsh on OS X, and this surprise bit me in bash on CentOS. I tried bash on OS X and found the same behavior: * does not match dot files. This seems very undesirable to me, but apparently it's the bash default. (It may be the zsh default too for all I remember, but I may have changed it years ago in my .zshrc and forgotten it ever worked differently.) How can I configure bash to behave as I expected: for * to match all files, and not ignore dot files. In case this is at all unclear, here's how to reproduce it cd /tmp mkdir {t,d}est touch test/{.,}{1,2,3,4,5,6,7} ls -hal test mv test/* dest ls -hal test # notice dot files are still there ls -hal dest # notice only some files were mv'ed |
I am restoring a database from a SQL Server Enterprise Edition onto a Standard Edition server. I keep getting an error stating: Database 'MyDatabase' cannot be started in this edition of SQL Server because part or all of object 'containedmemebersnapshots' is enabled with data compression or vardecimal storage format. Data compression and vardecimal storage format are only supported on SQL Server Enterprise Edition. As a result, my database is in suspect mode. Is there any resolution so I can restore this database onto SQL Server Standard Edition? | There is a requirement in our project where they want to evaluate if it is possible to downgrade SQL Server from Enterprise to Standard edition and if a server can be decommissioned. How can I identify which servers are suitable for downgrade? |
Prove that $(\mathbb{Z}/23\mathbb{Z})^*$ is generated by $5\pmod{23}$ Is there a tactic or theorem that could help me finding the power of $5\pmod{23}$ for each element? I was thinking about using Euler's theorem or Fermat's Little theorem, but I don't see how they could help me get for example $4\pmod{23}$ as generated by $5\pmod{23}$. Thanks in advance | I'm stuck on that question, because I'm trying to find a simple way to solve it. I'm pretty sure there exists such elements because the group is cyclic and $|\mathbb{Z}_{31}^{*}| = 30$, hence there exists a sub-group of any order dividing $30$. So I know there is a sub-group of order $10$ and it's cyclic because any sub-group of a cyclic group is cyclic, and it's generator is an elements of order $10$. Now, how can I proceed from here? How can one find the generator of this sub-group? |
I have an English course book that contains this question: Fill in the blank "The book is a set of techniques that systematically __ the learner for interaction with target language speakers". (A) prepare (B) preparing (C) prepares (D) prepared." The answer given in the book is A, but isn't C correct? I used Google and found this example "DNA technology is a powerful set of techniques that ALLOWS scientists to examine, change, and create new genetic material" | I'm having some issues with a sentence that is part of the purpose in a report that I'm writing. I'm not sure if the word "communicate" (in bold) should be singular or plural. The applications in the "set" will communicate with each other, not with other "sets". The purpose of this report is to develop a sample set of applications that communicates between services on the internet, mobile devices and a central processing unit in a motor vehicle. |
I am using Ubuntu 14.04. When I do Alt+Tab to switch windows, Ubuntu club the same type of tasks. For eg. If I have 2 Chrome windows, and 2 Firefox windows open, And I do Alt+Tab. I see only 2 and not 4 options. Now when I stay on a single Alt+Tab option for a few seconds it then shows me the windows inside it. That is not the case in linux mint. Linux Mint shows all the tabs for all the programs running when we do Alt+Tab. Is there a way, to do the same in Ubuntu --- not make it club the tasks when doing Alt+Tab? | When I use ALT+TAB to cycle through my apps I would like to have icons for all my open browsers. I use the ` (Grave or the key above TAB) but I really find that hard to use. Anyway I can just use ALT+TAB only? |
If $f,g:(X,A)\to (Y,B)$ are homotopic functions under a homotopy $H:X\times [0,1]\to Y$ such that $H(a,t)\in B$ for all $a\in A$ and $t\in [0,1]$, then $f_*=g_*:H_n(X,A)\to H_n(Y,B)$. This question has already been posted here and here but I still have many doubts, I would like to know where we are using that $f,g:(X,A)\to (Y,B)$ are homotopic in . I think it is enough to show that $f,g:X/A\to Y/B$ are homotopic, because in this case we already know that $f_*=g_*:H_n(X/A)\to H_n(Y/B)$ where $H_n(X/A)=H_n(X,A)$ and $H_n(Y/B)=H_n(Y,B)$. Now if $f,g:(X,A)\to (Y,B)$ are homotopic, how do I prove that $f,g:X/A\to Y/B$ are homotopic? Thank you. | Working with a homework problem: $X$ and $Y$ are topological spaces and $A\subset X$, $B\subset Y$. I have $f,g:(X,A)\to (Y,B)$ as homotopic maps. I need to show that the induced maps: $\hat{f},\hat{g}$ are homotopic. My instinct says that the homotopy I should use is $\hat{F}:I\times (X/A)\to (Y/B)$ should be given by $\hat{F}(t,[x]) := [F(t,x)]$. I showed this map is well defined without any problem. Edit: More precisely, $\hat{f}$ maps the pair $(t,[x])$, where $x$ is any element in $[x]\in X/A$, to $[y]$, where $y$ is any element in $[F(t,x)]$. But I'm having difficulty showing the map is continuous. If I take $V$ to be an open subset of $Y/B$, how can I use the continuity of $F$ to show that $\hat{F}$ is continuous? |
I downloaded the Stack Exchange app on my secondary phone (Android 6.0) and installed it. I tried to log in with my Google account. However, an error occurred. I tried the next day on my main phone (Android 5.1) and got the exact same error. Here is a screenshot: The version is the latest that is on the Play Store (latest update: 30 June 2017). I think that the error happens because the app's code is no longer compatible with Google's recent Play Services update. I sent an e-mail to the Stack Exchange developers about this (androidapp@stackexchange.com), however I did not get any response. So I thought that I would get a faster response here. Can anyone help me? | I tried logging in with a Google account, but I got the following error: |
I would really like to change my username in Minecraft, but I have to wait two days. I know it sounds stupid, but is there any way to speed up time in order to change it sooner? The username I chose was really, really stupid, so I'm eager to change it. | How do I change my name in minecraft name earlier than the 30 days please, I need help. My name is really dumb and I would like to change it early. I do not hack and I would like to change it early with NO hacks. I already looked up this question but I got no help . I tried looking up and I am quite impatient. is the link I used |
Help please. Our computer crashed and the world where my son had built his house vanished. I followed instructions I found on minecraft.gamepedia.com for recovering corrupted saved world data - replacing the following with ones from a new world - level.dat level.dat_mcr (not always present) level.dat_old session.lock This seemed to work but we couldn't find the houses we'd built or the lava pillar we built to mark the spot. We've flown around in all directions for long distances and found nothing. I didn't know about F3 and coordinates before we lost the world so we don't have any for our houses. There are beds in the houses but I'm not sure if we ever slept in them as we couldn't figure out how that worked and we're in creative mode. Is there any way to get the coordinates for our houses from the saved files for the world? Sorry if this question is not asked well - I'm a bit lost in this stuff but trying to recover it for my young son. | I wandered too far to go look for sheep and now I'm on a completely different island. How do I find my way back to my house? |
I created new role named "support" in my PostgreSQL. Now I need grant "READ ONLY" permissions for this role an ALL exists databases/tables. Also I need automatically granted same permissions on each DB that will created in future. I unsuccessfully tried next queries for grant permissions in new databases (Can not select from new database tables ): ALTER DEFAULT PRIVILEGES FOR ROLE support GRANT SELECT ON TABLES TO PUBLIC; ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES to support; I looked at , but it about all tables within single database. It not enough for me. | I want to GRANT SELECT ON ALL TABLES TO foo; But postgres tells me I have a syntax error at "TO". It expects a GRANT like: GRANT SELECT ON ALL TABLES IN SCHEMA public TO foo; We have a handful of tables that have been sharded such that public, shard123, and shard124 all have a table my_table, and public.my_table is the parent of both shard123.my_table and shard124.my_table. I've GRANTed SELECT to foo for public schema, but foo doesn't have permission for any of the shard schemas. I've also done: ALTER DEFAULT PRIVILEGES FOR ROLE dba GRANT SELECT ON TABLES TO foo; ...which should automatically grant for any new tables and schemas made from now on. There are 1000 < n < 10000 shards/schemas, so GRANTing separately for each shard/schema is impractical. How can I GRANT to a role for all existing tables across all existing schemas (all shards)? Or even better, can I GRANT for all schemas LIKE 'shard%'? |
I have been trying to set up a ConvNet to classify some data. This data should be classified to either 1 (being what I need to get from the image) and 0 for everything that is irrelevant. I have successfully extracted 50k samples (positive) but I am having a hard time of getting negative samples. What would happen if I trained my net with 15k positive samples and lets say 5k negative ? I have read that this could be a problem for statistical algorithms ... is that also relevant to convolutional neural networks ? | I deal with a fraud detection (credit-scoring-like) problem. As such there is a highly imbalanced relation between fraudulent and non-fraudulent observations. provides a great overview of different classification metrics. Precision and Recall or kappa both seem to be a good choice: One way to justify the results of such classifiers is by comparing them to those of baseline classifiers and showing that they are indeed better than random chance predictions. As far as I understand, kappa could be the slightly better choice here, as random chance is taken into account. From I understand that kappa deals with the concept of information gain: [...] an Observed Accuracy of 80% is a lot less impressive with an Expected Accuracy of 75% versus an Expected Accuracy of 50% [...] Therefore, my questions would be: Is it correct to assume kappa to be a better-suited classification metric for this problem? Does simply using kappa prevent the negative effects of imbalance on the classification algorithm? Is re-(down/up)-sampling or cost-based learning (see ) still required? |
I have installed Ubuntu version 15.04 on my laptop which already had windows 10 by partitioning the disk I have not yet stored any files in Ubuntu but found the installation process incomplete and is incompatible to install some softwares So I need to install Ubuntu version (18.04) which is downloaded and files are extracted into bootable pen drive Pls help me out | I would like to see a full how-to guide on how to install Ubuntu. |
Given $f$ is a bounded continuous function on $\mathbf{R}$ and $\mu$ is a probability measure such that for all $x \in \mathbf{R}$ $$ f(x) = \int_\mathbf{R}f(x+y)\mu(dy) $$ Please help to show that $f(x+s) = f(x)$ for all $s$ in the support of $\mu$. (The support of $\mu$ is the smallest set $E$ s.t. $\mu(E)=1$.) The hint is that we can try to use martingales to show $E[f(x+X_0)-f(x)]^2=0$, where $X_0$ has distribution $\mu$. So far I've constructed a martingale $M_n=f(x+S_n)$. Here $S_n = \sum_{j=1}^nX_j$ and $\{ X_j\}$ are i.i.d. with distribution $\mu$. But I've no idea on how to connect this martingale with the previous hint. I came cross another post about the same question on the forum, but it ends with the martingale that I stated here. So I'm wondering if anyone can provide some further insights about how to finish the proof. Since this is a hw problem, I've been working on it for three days only to get to this point. I sincerely appreciate any inputs that people will give. Thanks a ton! | Assume f is a bounded continuous function on $\mathbf{R}$ and $X$ is a random variable with distribution $F$. Assume for all $x \in \mathbf{R}$ that $$ f(x) = \int_\mathbf{R}f(x+y)F(dy) $$ Please help conclude that $f(x+s) = f(x)$ where $s$ is any value in the support of $F$. The hints that I have come across are to use Martingale theory and consider $\{ X_n\}$ to be i.i.d. with distribution $F$ and make a martingale with some function of $S_n = \sum_{j=1}^nX_j$. Thanks! |
I was calculating potential energy due to point charge at origin using relationship $$U=\dfrac{1}{2}\epsilon_{0}\displaystyle\int \mathbf {\vec E.\vec E\ } \ d\tau$$ and it comes out to be infinity because $\mathbf {\vec E.\vec E\ }=|\vec E|^2 $ falls off as $\propto$ $\dfrac{1}{r^4}$ and volume $d\tau$ grows as $4\pi r^2 dr$ resulting in overall fall off as $\propto$ $\dfrac{dr}{r^2}$ and which in turn lead to blowing up of integral at $r=0$ and U approaching $\infty$ Question: it is written in my textbook as it is that: "it takes infinite energy to pack a point charge(like electrons, protons) into zero volume." i want to know physical justification of this result (not mathematical derivation like above ) | I will try to limit the question in the case of the electric fields, but is something that applies also to the magnetic ones. There are two ways to express the energy in a capacitor: By Voltage : $U = 1/2 CV^2 $ And by Field : $U = 1/2 \varepsilon E^2Ad$, With Energy Density: $u = 1/2 \varepsilon E^2 $ Unless i understood everything wrong and these two are NOT the same quantity, i have the following question. When we have two charges placed at points A and B, then in order to calculate the energy of the system, we will take the first charge, place it at point A WITHOUT doing any work, and then we will calculate the work needed to place the second charge at point B. The weird thing to me here, is that while we have placed the first charge, without generating any work the system will still have the energy held in the field of the charge! There is obviously something that i miss, but what? |
\documentclass{article} \begin{document} ${x_i}^j$ works as expected but not with an hat as in ${\hat{x}_i}^j$. The way I found to make it work is $\mbox{$\hat{x}_i$}^j$. Is there an nicer solution? \end{document} | I like how there is a gap between the subscript and the superscript when I write ${w_i}^T$. However, if I try to put a hat on the vector, like $\hat{w}_i^T$, this space goes away. Any ideas? I tried putting in an extra set of braces, as suggested for a similar question , but it didn't work. |
I've been playing for about 3 years with this guy on my group. He's a very nice and encouraging person and I actually appreciate him as an individual; however I just can't come to enjoy his presence as a Player. His characters make me feel quite uncomfortable, since he always makes them way too virtuous and likes to steal the scene. His characters are either made to "troll" or lecture villains, and are also made without a trace of negative traits; they're shining examples which can get very obnoxious since he just likes to think about them as undefeated heroes, and gets quite upset when a monster or villain stomp on him... I actually think I make my best effort to kill his characters and render them useless, since he often outshines the rest of my players and talking to him isn't working. He likes to aid the party members, but takes every chance to lecture them or make a display of heroism and concern so he can steal the spotlight and start talking. All of us, the remaining 4 (including me) on the table dislike this, however none of us want to kick him out not only because he's a good friend, but because we had an incredibly hard time getting together to roleplay since we're not on a country in which roleplaying is even remotely popular, specially with our favorite system (Anima: Beyond Fantasy). We agreed to talk to him, TWO TIMES, but twice, my players shied away and I was left alone to talk to him without results. This guy wants to have a one player role playing game with him, and I don't know what to do. I haven't played in a while and I'm craving to do so, however I don't know how to actually like the characters he makes. | In my time as a GM, I've always hated stuff such as magic items, artifacts, etc; even as a player, I dislike the feeling of becoming "too cool" for the game world in question. However, I have a player that just likes coolness and is always expecting to find magic items, artifacts, and gain cool abilities. He isn't a "Power Gamer" per-se, since he favors roleplaying and getting whatever fits his "style" instead of the most damaging stuff, however I feel he always wants to be the coolest of the group. Playing D&D for example, he had a Monk, and he wanted to have a magical gourd of liquor that lets him spit a fire cone, and he ALSO wanted Wukong's Magical Cloud, and ALSO wanted to be the best friend and disciple of the god Korada from PF and pretty much "dedicate" a whole adventure arc on it. Playing Pokemon Tabletop Untied, he's been desperately looking for a way to be able to have A LOT of combats mounted on his dragon Pokemons, I haven't, but he's always making comments on the subject, and he wants to be surrounded by said scenes of aerial badassery and combat. On Savage Worlds, he made a character with "Weird Science" that can summon swords from books (LOTR, Narnia, etc), but he wants to make the game go long enough so he can have the 49 swords he imagined, he gave me the list, and usually takes forever to describe his actions with such swords even tho the resolution of said is simple. Players haven't complaied about it, but I just dislike the fact he wants to be the coolest guy on town every time, and that he centers his characters on the concept "be as cool as I can", specially since he makes them in such way they're moraly "perfect" and have no exploitable negative attitudes, heck, even with SW Hindrance system he picks Hindrances that make him look like a perfect, flawless individual like "Loyal" or "Quirk: Too Heroic". I don't want to shoo him from my table, because he's one of my best friends, I just wanna deal with this. |
There seems to be a small bug that can cause inconsistent order of the active questions list on the homepage: This is the first time I see that. This was on electronics.stackexchange. The inconsistency was already there a few seconds before I refreshed the page and took the screenshot, but was fixed after refreshing a few minutes later. | I've noticed a strange little issue, which is most likely related to caching. When I'm on the homepage of a Stack Exchange site (not on Stack Overflow), it would occationally tell me that there's new activity, and that I should click the banner to update: When clicked: However, when I refresh the page, I still get the outdated, cached version of the page for several minutes. If the information about an update is available, shouldn't that invalidate the cache? I mean, the server knows for sure that there's new content available... |
I am getting the following error in the top menu bar: An error occurred. Please run the Package Manager from the right-click menu or apt-get in a terminal to see what is wrong. The error message was:'Error:BrokenCount>0'. | I am getting the following error in the top menu bar: An error occurred.Please run the Package Manger form the right-click menu or apt-get in a terminal to see what is wrong.The error message was:'Error:BrokenCount>0'.This usually means that your installed packages have unmet dependencies. |
I own a machine that is running Windows 8.1 Pro 64-bit. It has an user account with limited rights - where I can login and the Administrator account for which i forgot the password. Both accounts are local and the computer doesn't belong to a domain. Is there any possible way of resetting or removing the Administrator password? | I got a brand new Windows 7 machine, installed the operating system, created one account and forgot its password. What can I do? There is no external CD, the operating system is loaded from somewhere inside the machine. I already tried to remember passwords and tried all candidates with all possible combinations of caps lock, num lock etc. |