DiscreteHadamardTransform
DiscreteHadamardTransform[list] gives the discrete Hadamard transform of list.
Examples
Compute the discrete Hadamard transform of a list:
DiscreteHadamardTransform[{1, 2, 3, 4}]
(* {5, -1, -2, 0} *)Please visit the official Wolfram Language Reference for more details.