Fast Walsh Hadamard Transform, is an Hadamard ordered efficient algorithm to compute the Walsh Hadamard transform (WHT). Normal WHT computation has N = 2m complexity but using FWHT reduces the computation to O(n2). The FWHT requires O(n logn) additions and subtraction operations. It is a divide and conquer algorithm which breaks down the WHT recursively.
sympy.discrete.transforms.fwht( ) : It can perform Walsh Hadamard Transform (WHT). This method uses Hadamard sequence ordering.
Automatically the sequence is padded with zero to the right because the radix-2 FWHT requires the sample point number as a power of 2.
Parameters : -> seq : [iterable] sequence on which WHT is to be applied. Returns : Fast Walsh Hadamard Transform Transform
Example #1 :
Python3
# import sympy from sympy import fwht# sequence seq = [23, 56, 12, 555]# hwhttransform = fwht(seq)print ("Transform : ", transform) |
Output :
Transform : [646, -576, -488, 510]
Example #2 :
Python3
# import sympy from sympy import fwht# sequence seq = [15, 21, 13, 44]# hwhttransform = fwht(seq)print ("Transform : ", transform) |
Output :
Transform : [93, -37, -21, 25]
