numpy.delete删除列的方法

numpy.delete
numpy.delete(arr, obj, axis=None)[source]
 Return a new array with sub-arrays along an axis deleted. For a one dimensional array, this returns those entries not returned by arr[obj].
 Parameters:	
 arr : array_like
 Input array.
 obj : slice, int or array of ints
 Indicate which sub-arrays to remove.
 axis : int, optional
 The axis along which to delete the subarray defined by obj. If axis is None, obj is applied to the flattened array.
 Returns:	
 out : ndarray
 A copy of arr with the elements specified by obj removed. Note that delete does not occur in-place. If axis is None, out is a flattened array.

>>> dataset=[[1,2,3],[2,3,4],[4,5,6]] 
>>> import numpy as np 
>>> dataset = np.delete(dataset, -1, axis=1) 
>>> dataset 
array([[1, 2], 
 [2, 3], 
 [4, 5]])

arr = np.array([[1,2,3,4], [5,6,7,8], [9,10,11,12]]) 
np.delete(arr, [1,2], axis=1) 
array([[ 1, 4], 
 [ 5, 8], 
 [ 9, 12]])