pydiodon.centering_operator

pydiodon.centering_operator(m)[source]

Centering operator for a matrix

will probably be deprecated (22.09.21)

argument

m : an integer ; vector or matrix dimension

returns

H: a numpy array, m x m

Notes

If A is a n x p matrix

  • \(HA\) is A with centered columns (H is n x n)

  • \(AH\) is A with centered row (H is p x p)

example

>>> import pydiodon as dio
>>> import numpy as np
>>> n = 4 ; p = 3
>>> A = np.arange(n*p)
>>> A.shape = (n,p)
>>> H_row = dio.centering_operator(p)
>>> H_col = dio.centering_operator(n)
>>> Ar = A @ H_row
>>> Ac = H_col @ A

revised 21.02.27