Remove mean from numpy matrix

Question

I have a numpy matrix A where the data is organised column-vector-vise i.e A[:,0] is the first data vector, A[:,1] is the second and so on

Answer 1

Looks like some of these answers are pretty old, I just tested this on numpy 1.13.3:

>>> import numpy as np
>>> a = np.array([[1,1,3],[1,0,4],[1,2,2]])
>>> a
array([[1, 1, 3],
       [1, 0, 4],
       [1, 2, 2]])
>>> a = a - a.mean(axis=0)
>>> a
array([[ 0.,  0.,  0.],
       [ 0., -1.,  1.],
       [ 0.,  1., -1.]])

I think this is much cleaner and simpler. Have a try and let me know if this is somehow inferior than the other answers.