Skip to content

Pythoneo

Online How to Python stuff

How to count number of zeros in Numpy array?

Posted on April 29, 2021April 1, 2022 By Luke K

Let’s check how many zeros the are in your array. We will use Numpy count_nonzero function.
Numpy count number of zeros

Using count_nonzero method

To check how many zeros you have in your array you need to know count_nonzero function.

Just put my_array==0 as an argument as in below example.

import numpy as np

my_array = np.array([0, 7, 6, 5,
                     0, 0, 0, 7,
                     0, 3, 2, 0])

zeros = np.count_nonzero(my_array == 0)

print(f"There are {zeros} zeros in my array.")

Numpy count number of zeros

As you can see Python printed out the number of zeros from the array.

See also  How to generate random matrix in Numpy?

Using where method

Another way to count number of zeros in an array would be to use Numpy where method.


import numpy as np

my_array = np.array([0, 7, 6, 5,
                     0, 0, 0, 7,
                     0, 3, 2, 0])

zeros = my_array[np.where(my_array == 0)]

print(f"There are {zeros.size} zeros in my array.")

Thanks to Numpy where function it is possible to create additional zeros array which contains only zeros. The answer would be the size of zeros array.

See also  How to convert numpy to xyz file?

The output would be:

There are 6 zeros in my array.
numpy Tags:array, count, zero

Post navigation

Previous Post: How to check if array is empty?
Next Post: How many distinct values in array?

Categories

  • bokeh (1)
  • datetime (3)
  • Django (1)
  • glob (1)
  • io (1)
  • json (1)
  • math (4)
  • matplotlib (9)
  • numpy (84)
  • OpenCV (1)
  • os (3)
  • Pandas (2)
  • pathlib (2)
  • Pillow (3)
  • Plotly (1)
  • Python (25)
  • random (7)
  • requests (1)
  • Scipy (4)
  • Seaborn (3)
  • shutil (1)
  • sqlite3 (1)
  • statistics (16)
  • sys (1)
  • Tkinter (9)
  • turtle (2)
  • urllib (1)
  • webbrowser (1)

RSS RSS

  • How to use curdoc in Bokeh
  • How to solve TypeError: ‘set’ object is not subscriptable
  • How to calculate the factorial of an array in Numpy?
  • How to Make a Countplot in Seaborn
  • AttributeError: partially initialized module ‘cv2’ has no attribute ‘img’ (most likely due to a circular import)
  • How to enumerate dictionary in Python?
  • How to compare two arrays in Numpy?
  • How to square a matrix in Numpy?
  • Exploding out slices of a Pie Chart in Plotly
  • How to uninstall Numpy?

Tags

arithmetic mean array axis button calculations chart conversion copy count counter data type dictionary dimension draw error files fill float generate grid GUI image index integer list matrix max mean median min normal distribution plot random reshape rotate round size standard deviation string sum test text time variance zero

Copyright © 2023 Pythoneo.

Powered by PressBook WordPress theme

We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies.
Cookie settingsACCEPT
Manage consent

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Non-necessary
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
SAVE & ACCEPT