Copy an numpy Array in Python

In this article we will look at how to copy a numpy array to another array

Lets look at some examples

Example 1

First of all lets use the equals operator to copy the complete Numpy Array to another one.

import numpy as np

originalarray = np.array([10, 20, 30, 40, 50])

copyarray = originalarray

print("Original Array = ", originalarray)
print("Copied Array   = ", copyarray)

Lets run this and as expected you will see

>>> %Run numpyarraycopy1.py
Original Array =  [10 20 30 40 50]
Copied Array   =  [10 20 30 40 50]

Example 2

Using a for loop with range

import numpy as np

originalarray = np.array([12, 22, 35, 55, 47])
copyarray = np.empty(5)

for i in range(len(originalarray)):
    copyarray[i] = originalarray[i]

print("Original Array = ", originalarray)
print("Copy Of Array   = ", copyarray)

This is what you will get when you run this example

>>> %Run numpyarraycopy2.py
Original Array =  [10 20 30 40 50]
Copy Of Array   =  [10. 20. 30. 40. 50.]

Example 3

import numpy as np

originalarray = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])

copyarray1 = originalarray
copyarray2 = originalarray[3:7]
copyarray3 = originalarray[4:]
copyarray4 = originalarray[::-1]

print("Original Array = ", originalarray)
print("Copied Array   = ", copyarray1)
print("Copy Array Items 4 to 7   = ", copyarray2)
print("Copy Array Items 5 to End   = ", copyarray3)
print("Reverse Array   = ", copyarray4)

This is what you will get when you run this example

>>> %Run numpyarraycopy3.py
Original Array =  [ 1  2  3  4  5  6  7  8  9 10]
Copied Array   =  [ 1  2  3  4  5  6  7  8  9 10]
Copy Array Items 4 to 7   =  [4 5 6 7]
Copy Array Items 5 to End   =  [ 5  6  7  8  9 10]
Reverse Array   =  [10  9  8  7  6  5  4  3  2  1]

Links

The examples are on github

They are called numpyarraycopy1, numpyarraycopy2 and numpyarraycopy3