# -*- coding: utf-8 -*-
# mathtoolspy
# -----------
# A fast, efficient Python library for mathematically operations, like
# integration, solver, distributions and other useful functions.
#
# Author: sonntagsgesicht, based on a fork of Deutsche Postbank [pbrisk]
# Version: 0.3, copyright Wednesday, 18 September 2019
# Website: https://github.com/sonntagsgesicht/mathtoolspy
# License: Apache License 2.0 (see LICENSE file)
"""
The MathFct contains some mathematically method, which are not supported by the Python lib.
"""
import operator
from .mathconst import DOUBLE_TOL
from functools import reduce
[docs]def abs_sign(a, b):
''' The absolute value of A with the sign of B.'''
return abs(a) if b >= 0 else -abs(a)
[docs]def sign(x):
'''
Returns the sign of the double number x.
-1 if x < 0; 1 if x > 0 and 0 if x == 0
'''
if x < 0:
return -1
elif x > 0:
return 1
else:
return 0
[docs]def float_equal(x, y, tol=DOUBLE_TOL):
return abs(x - y) < tol
[docs]def prod(factors):
"""
The product of the given factors (iterable)
:param factors:
:return:
"""
return reduce(operator.mul, factors, 1.0)
[docs]def get_grid(start, end, nsteps=100):
"""
Generates a equal distanced list of float values with nsteps+1 values, begining start and ending with end.
:param start: the start value of the generated list.
:type float
:param end: the end value of the generated list.
:type float
:param nsteps: optional the number of steps (default=100), i.e. the generated list contains nstep+1 values.
:type int
"""
step = (end-start) / float(nsteps)
return [start + i * step for i in range(nsteps+1)]
[docs]class FctWithCount(object):
def __init__(self, fct):
self.fct = fct
self.number_of_calls = 0
def __call__(self, x):
self.number_of_calls += 1
return self.fct(x)
[docs]class CompositionFct:
def __init__(self, *fcts):
self.fcts = fcts[::-1]
def __call__(self, x):
ret = x
for fct in self.fcts:
ret = fct(ret)
return ret