import numpy as np
A = np.array([[1,2],[13,4],[5,6]])
print(A.shape)
b = np.compress([0,1],A,axis=0)
#compress is something like 'bool' picking, array A has 3 lines, 2 columns, when axis= 0, it goes to 'pick' at line, and the 'condition' is the 'False/Ture' indicator to each line in arry, 'Ture' is YES, False is NO.
print(b)
OUTPUT:
[[13 4]]