Functor for the CONST projector.
A, the image matrix, is such that A == C.
>>> from numpy.random import rand, seed
>>> import numpy as np
>>> M = np.round(
rand(5,5), decimals=2)
>>> C = np.round(
rand(5,5), decimals=2)
>>> p = const(C)
>>> C
array([[0.79, 0.2 , 0.51, 0.59, 0.05],
[0.61, 0.17, 0.07, 0.95, 0.97],
[0.81, 0.3 , 0.1 , 0.68, 0.44],
[0.12, 0.5 , 0.03, 0.91, 0.26],
[0.66, 0.31, 0.52, 0.55, 0.18]])
>>> M
array([[0.37, 0.95, 0.73, 0.6 , 0.16],
[0.16, 0.06, 0.87, 0.6 , 0.71],
[0.02, 0.97, 0.83, 0.21, 0.18],
[0.18, 0.3 , 0.52, 0.43, 0.29],
[0.61, 0.14, 0.29, 0.37, 0.46]])
>>> p(M)
array([[0.79, 0.2 , 0.51, 0.59, 0.05],
[0.61, 0.17, 0.07, 0.95, 0.97],
[0.81, 0.3 , 0.1 , 0.68, 0.44],
[0.12, 0.5 , 0.03, 0.91, 0.26],
[0.66, 0.31, 0.52, 0.55, 0.18]])