114 lines
3.2 KiB
Python
114 lines
3.2 KiB
Python
# Copyright 2010-2022 Google LLC
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
"""helpers methods for the cp_model module."""
|
|
|
|
import numbers
|
|
import numpy as np
|
|
|
|
INT_MIN = -9223372036854775808 # hardcoded to be platform independent.
|
|
INT_MAX = 9223372036854775807
|
|
INT32_MIN = -2147483648
|
|
INT32_MAX = 2147483647
|
|
|
|
|
|
def is_integral(x):
|
|
"""Checks if x has either a number.Integral or a np.integer type."""
|
|
return isinstance(x, numbers.Integral) or isinstance(x, np.integer)
|
|
|
|
|
|
def is_a_number(x):
|
|
"""Checks if x has either a number.Number or a np.double type."""
|
|
return (
|
|
isinstance(x, numbers.Number)
|
|
or isinstance(x, np.double)
|
|
or isinstance(x, np.integer)
|
|
)
|
|
|
|
|
|
def is_zero(x):
|
|
"""Checks if the x is 0 or 0.0."""
|
|
return (is_integral(x) and int(x) == 0) or (is_a_number(x) and float(x) == 0.0)
|
|
|
|
|
|
def is_one(x):
|
|
"""Checks if x is 1 or 1.0."""
|
|
return (is_integral(x) and int(x) == 1) or (is_a_number(x) and float(x) == 1.0)
|
|
|
|
|
|
def is_minus_one(x):
|
|
"""Checks if x is -1 or -1.0."""
|
|
return (is_integral(x) and int(x) == -1) or (is_a_number(x) and float(x) == -1.0)
|
|
|
|
|
|
def assert_is_int64(x):
|
|
"""Asserts that x is integer and x is in [min_int_64, max_int_64]."""
|
|
if not is_integral(x):
|
|
raise TypeError("Not an integer: %s" % x)
|
|
if x < INT_MIN or x > INT_MAX:
|
|
raise OverflowError("Does not fit in an int64_t: %s" % x)
|
|
return int(x)
|
|
|
|
|
|
def assert_is_int32(x):
|
|
"""Asserts that x is integer and x is in [min_int_32, max_int_32]."""
|
|
if not is_integral(x):
|
|
raise TypeError("Not an integer: %s" % x)
|
|
if x < INT32_MIN or x > INT32_MAX:
|
|
raise OverflowError("Does not fit in an int32_t: %s" % x)
|
|
return int(x)
|
|
|
|
|
|
def assert_is_boolean(x):
|
|
"""Asserts that x is 0 or 1."""
|
|
if not is_integral(x) or x < 0 or x > 1:
|
|
raise TypeError("Not a boolean: %s" % x)
|
|
|
|
|
|
def assert_is_a_number(x):
|
|
"""Asserts that x is a number and returns it."""
|
|
if not is_a_number(x):
|
|
raise TypeError("Not a number: %s" % x)
|
|
elif is_integral(x):
|
|
return int(x)
|
|
else:
|
|
return float(x)
|
|
|
|
|
|
def to_capped_int64(v):
|
|
"""Restrict v within [INT_MIN..INT_MAX] range."""
|
|
if v > INT_MAX:
|
|
return INT_MAX
|
|
if v < INT_MIN:
|
|
return INT_MIN
|
|
return v
|
|
|
|
|
|
def capped_subtraction(x, y):
|
|
"""Saturated arithmetics. Returns x - y truncated to the int64_t range."""
|
|
assert_is_int64(x)
|
|
assert_is_int64(y)
|
|
if y == 0:
|
|
return x
|
|
if x == y:
|
|
if x == INT_MAX or x == INT_MIN:
|
|
raise OverflowError("Integer NaN: subtracting INT_MAX or INT_MIN to itself")
|
|
return 0
|
|
if x == INT_MAX or x == INT_MIN:
|
|
return x
|
|
if y == INT_MAX:
|
|
return INT_MIN
|
|
if y == INT_MIN:
|
|
return INT_MAX
|
|
return to_capped_int64(x - y)
|