# numpy.stack() in Python with example.

In this tutorial, we are going to learn how to use numpy.stack() method in Python with simple programs.

Firstly, this method is mainly used for combining a sequence of equal dimension arrays along with a new axis.

## numpy.stack() in Python

Numpy stands for Numerical Python.

By using numpy.stack() method we can join the sequence of the equal size arrays based on the axis value(index value for simple understanding).

#### syntax:

numpy.stack(array,axis)

**array:** it is a sequence of array of the same size.

**axis:** The axis in the consequent array along which the input arrays are sequenced/stacked.

- the axis defines the index of the new axis in the result.
- axis=0 indicates the starting dimension.
- axis=-1 indicates the last dimension.

#### Example code 1:

import numpy as cp x=cp.array([[1,3],[5,7]]) print'First array list:' print x print'\n' y=cp.array([[2,4][6,8]]) print'Second array list:' print y print'\n' print'joining the two arrays along axis 0:' print cp.stack((x,y),0) print'\n' print 'joining the two arrays along axis 1:' print cp.stack((x,y),1)

First array list: [[1 3] [5 7]] Second array list: [[2 4] [6 8]] joining the two arrays along axis 0: [[[1 3] [5 7]] [[2 4] [6 8]]] joining the two arrays along axis 1: [[[1 3] [2 4]] [[5 7] [6 8]]]

we will see another code as an example so, It makes you understand In brief.

#### Example 2:

# Example programme for numpy.stack() in python import numpy as cp array1=cp.array([0,1,2]) print("First array is:\n",array1) array2=cp.array([3,4,5]) print("Second array is:\n",array2) #joining the two arrays along axis 0 result1=cp.stack((array1,array2),axis=0) print("resultant array along axis 0:\n",result1) #joining the two arrays along axis 1 result2=cp.stack((array1,array2),axis=1) print("resultant array along axis 1:",result2)

First array is: [0 1 2] Second array is: [3 4 5] resultant array along axis 0: [[0 1 2] [3 4 5]] resultant array along axis 1: [[0 3] [1 4] [2 5]]

also, read rfind method in python

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