How to delete columns in numpy.array
Given its name, I think the standard way should be delete
:
import numpy as np
A = np.delete(A, 1, 0) # delete second row of A
B = np.delete(B, 2, 0) # delete third row of B
C = np.delete(C, 1, 1) # delete second column of C
According to numpy's documentation page, the parameters for numpy.delete
are as follow:
numpy.delete(arr, obj, axis=None)
arr
refers to the input array,obj
refers to which sub-arrays (e.g. column/row no. or slice of the array) andaxis
refers to either column wise (axis = 1
) or row-wise (axis = 0
) delete operation.
Example from the numpy documentation:
>>> a = numpy.array([[ 0, 1, 2, 3],
[ 4, 5, 6, 7],
[ 8, 9, 10, 11],
[12, 13, 14, 15]])
>>> numpy.delete(a, numpy.s_[1:3], axis=0) # remove rows 1 and 2
array([[ 0, 1, 2, 3],
[12, 13, 14, 15]])
>>> numpy.delete(a, numpy.s_[1:3], axis=1) # remove columns 1 and 2
array([[ 0, 3],
[ 4, 7],
[ 8, 11],
[12, 15]])