mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-11-30 16:31:08 +00:00
373f193c6d
* Correcting the Gaussian Formula I have added the parenthesis around the 2*sigma^2 term. * Update gaussian.py * Update gaussian.py * Update gaussian.py * Update gaussian.py * Update gaussian.py * Update gaussian.py Co-authored-by: Christian Clauss <cclauss@me.com>
62 lines
1.6 KiB
Python
62 lines
1.6 KiB
Python
"""
|
|
Reference: https://en.wikipedia.org/wiki/Gaussian_function
|
|
"""
|
|
from numpy import exp, pi, sqrt
|
|
|
|
|
|
def gaussian(x, mu: float = 0.0, sigma: float = 1.0) -> int:
|
|
"""
|
|
>>> gaussian(1)
|
|
0.24197072451914337
|
|
|
|
>>> gaussian(24)
|
|
3.342714441794458e-126
|
|
|
|
>>> gaussian(1, 4, 2)
|
|
0.06475879783294587
|
|
|
|
>>> gaussian(1, 5, 3)
|
|
0.05467002489199788
|
|
|
|
Supports NumPy Arrays
|
|
Use numpy.meshgrid with this to generate gaussian blur on images.
|
|
>>> import numpy as np
|
|
>>> x = np.arange(15)
|
|
>>> gaussian(x)
|
|
array([3.98942280e-01, 2.41970725e-01, 5.39909665e-02, 4.43184841e-03,
|
|
1.33830226e-04, 1.48671951e-06, 6.07588285e-09, 9.13472041e-12,
|
|
5.05227108e-15, 1.02797736e-18, 7.69459863e-23, 2.11881925e-27,
|
|
2.14638374e-32, 7.99882776e-38, 1.09660656e-43])
|
|
|
|
>>> gaussian(15)
|
|
5.530709549844416e-50
|
|
|
|
>>> gaussian([1,2, 'string'])
|
|
Traceback (most recent call last):
|
|
...
|
|
TypeError: unsupported operand type(s) for -: 'list' and 'float'
|
|
|
|
>>> gaussian('hello world')
|
|
Traceback (most recent call last):
|
|
...
|
|
TypeError: unsupported operand type(s) for -: 'str' and 'float'
|
|
|
|
>>> gaussian(10**234) # doctest: +IGNORE_EXCEPTION_DETAIL
|
|
Traceback (most recent call last):
|
|
...
|
|
OverflowError: (34, 'Result too large')
|
|
|
|
>>> gaussian(10**-326)
|
|
0.3989422804014327
|
|
|
|
>>> gaussian(2523, mu=234234, sigma=3425)
|
|
0.0
|
|
"""
|
|
return 1 / sqrt(2 * pi * sigma ** 2) * exp(-((x - mu) ** 2) / (2 * sigma ** 2))
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import doctest
|
|
|
|
doctest.testmod()
|