numpy常用矩阵操作

1.删除列

column_to_delete = [0, 1, 2]
arr = np.delete(arr, [0, 1, 2], axis=1)

2.归一化

arr = normalize(arr, axis=0, norm='max')

3.取某几列

column_to_get = [1, 3, 5]
arr = np.array(arr[:, column_to_get], dtype=np.float)