numpy.column_stack() in Python

numpy.column_stack() function is used to stack 1-D arrays as columns into a 2-D array.It takes a sequence of 1-D arrays and stack them as columns to make a single 2-D array. 2-D arrays are stacked as-is, just like with hstack function.

Syntax : numpy.column_stack(tup)

Parameters :
tup : [sequence of ndarrays] Tuple containing arrays to be stacked. The arrays must have the same first dimension.
Return : [stacked 2-D array] The stacked 2-D array of the input arrays.

Code #1 :

# Python program explaining
# column_stack() function

import numpy as geek

# input array
in_arr1 = geek.array(( 1, 2, 3 ))
print ("1st Input array : \n", in_arr1)

in_arr2 = geek.array(( 4, 5, 6 ))
print ("2nd Input array : \n", in_arr2)

# Stacking the two arrays
out_arr = geek.column_stack((in_arr1, in_arr2))
print ("Output stacked array:\n ", out_arr)

Output:

1st Input array : 
 [1 2 3]
2nd Input array : 
 [4 5 6]
Output stacked array:
  [[1 4]
 [2 5]
 [3 6]]

Code #2 :

# Python program explaining
# column_stack() function

import numpy as geek

# input array
in_arr1 = geek.array([[ 1, 2, 3], [ -1, -2, -3]] )
print ("1st Input array : \n", in_arr1)

in_arr2 = geek.array([[ 4, 5, 6], [ -4, -5, -6]] )
print ("2nd Input array : \n", in_arr2)

# Stacking the two arrays
out_arr = geek.column_stack((in_arr1, in_arr2))
print ("Output stacked array :\n ", out_arr)

Output:

1st Input array : 
 [[ 1  2  3]
 [-1 -2 -3]]
2nd Input array : 
 [[ 4  5  6]
 [-4 -5 -6]]
Output stacked array :
  [[ 1  2  3  4  5  6]
 [-1 -2 -3 -4 -5 -6]]