File size: 6,223 Bytes
6370773 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 |
#!/usr/bin/env python3
"""Prints type-coercion tables for the built-in NumPy types
"""
import numpy as np
from numpy._core.numerictypes import obj2sctype
from collections import namedtuple
# Generic object that can be added, but doesn't do anything else
class GenericObject:
def __init__(self, v):
self.v = v
def __add__(self, other):
return self
def __radd__(self, other):
return self
dtype = np.dtype('O')
def print_cancast_table(ntypes):
print('X', end=' ')
for char in ntypes:
print(char, end=' ')
print()
for row in ntypes:
print(row, end=' ')
for col in ntypes:
if np.can_cast(row, col, "equiv"):
cast = "#"
elif np.can_cast(row, col, "safe"):
cast = "="
elif np.can_cast(row, col, "same_kind"):
cast = "~"
elif np.can_cast(row, col, "unsafe"):
cast = "."
else:
cast = " "
print(cast, end=' ')
print()
def print_coercion_table(ntypes, inputfirstvalue, inputsecondvalue, firstarray, use_promote_types=False):
print('+', end=' ')
for char in ntypes:
print(char, end=' ')
print()
for row in ntypes:
if row == 'O':
rowtype = GenericObject
else:
rowtype = obj2sctype(row)
print(row, end=' ')
for col in ntypes:
if col == 'O':
coltype = GenericObject
else:
coltype = obj2sctype(col)
try:
if firstarray:
rowvalue = np.array([rowtype(inputfirstvalue)], dtype=rowtype)
else:
rowvalue = rowtype(inputfirstvalue)
colvalue = coltype(inputsecondvalue)
if use_promote_types:
char = np.promote_types(rowvalue.dtype, colvalue.dtype).char
else:
value = np.add(rowvalue, colvalue)
if isinstance(value, np.ndarray):
char = value.dtype.char
else:
char = np.dtype(type(value)).char
except ValueError:
char = '!'
except OverflowError:
char = '@'
except TypeError:
char = '#'
print(char, end=' ')
print()
def print_new_cast_table(*, can_cast=True, legacy=False, flags=False):
"""Prints new casts, the values given are default "can-cast" values, not
actual ones.
"""
from numpy._core._multiarray_tests import get_all_cast_information
cast_table = {
-1: " ",
0: "#", # No cast (classify as equivalent here)
1: "#", # equivalent casting
2: "=", # safe casting
3: "~", # same-kind casting
4: ".", # unsafe casting
}
flags_table = {
0 : "▗", 7: "█",
1: "▚", 2: "▐", 4: "▄",
3: "▜", 5: "▙",
6: "▟",
}
cast_info = namedtuple("cast_info", ["can_cast", "legacy", "flags"])
no_cast_info = cast_info(" ", " ", " ")
casts = get_all_cast_information()
table = {}
dtypes = set()
for cast in casts:
dtypes.add(cast["from"])
dtypes.add(cast["to"])
if cast["from"] not in table:
table[cast["from"]] = {}
to_dict = table[cast["from"]]
can_cast = cast_table[cast["casting"]]
legacy = "L" if cast["legacy"] else "."
flags = 0
if cast["requires_pyapi"]:
flags |= 1
if cast["supports_unaligned"]:
flags |= 2
if cast["no_floatingpoint_errors"]:
flags |= 4
flags = flags_table[flags]
to_dict[cast["to"]] = cast_info(can_cast=can_cast, legacy=legacy, flags=flags)
# The np.dtype(x.type) is a bit strange, because dtype classes do
# not expose much yet.
types = np.typecodes["All"]
def sorter(x):
# This is a bit weird hack, to get a table as close as possible to
# the one printing all typecodes (but expecting user-dtypes).
dtype = np.dtype(x.type)
try:
indx = types.index(dtype.char)
except ValueError:
indx = np.inf
return (indx, dtype.char)
dtypes = sorted(dtypes, key=sorter)
def print_table(field="can_cast"):
print('X', end=' ')
for dt in dtypes:
print(np.dtype(dt.type).char, end=' ')
print()
for from_dt in dtypes:
print(np.dtype(from_dt.type).char, end=' ')
row = table.get(from_dt, {})
for to_dt in dtypes:
print(getattr(row.get(to_dt, no_cast_info), field), end=' ')
print()
if can_cast:
# Print the actual table:
print()
print("Casting: # is equivalent, = is safe, ~ is same-kind, and . is unsafe")
print()
print_table("can_cast")
if legacy:
print()
print("L denotes a legacy cast . a non-legacy one.")
print()
print_table("legacy")
if flags:
print()
print(f"{flags_table[0]}: no flags, {flags_table[1]}: PyAPI, "
f"{flags_table[2]}: supports unaligned, {flags_table[4]}: no-float-errors")
print()
print_table("flags")
if __name__ == '__main__':
print("can cast")
print_cancast_table(np.typecodes['All'])
print()
print("In these tables, ValueError is '!', OverflowError is '@', TypeError is '#'")
print()
print("scalar + scalar")
print_coercion_table(np.typecodes['All'], 0, 0, False)
print()
print("scalar + neg scalar")
print_coercion_table(np.typecodes['All'], 0, -1, False)
print()
print("array + scalar")
print_coercion_table(np.typecodes['All'], 0, 0, True)
print()
print("array + neg scalar")
print_coercion_table(np.typecodes['All'], 0, -1, True)
print()
print("promote_types")
print_coercion_table(np.typecodes['All'], 0, 0, False, True)
print("New casting type promotion:")
print_new_cast_table(can_cast=True, legacy=True, flags=True)
|