sciPy stats.nanstd() function | Python Last Updated : 11 Feb, 2019 Comments Improve Suggest changes Like Article Like Report scipy.stats.nanstd(array, axis=0) function calculates the standard deviation by ignoring the Nan (not a number) values of the array elements along the specified axis of the array. It's formula - Parameters : array : Input array or object having the elements, including Nan values, to calculate the standard deviation. axis : Axis along which the standard deviation is to be computed. By default axis = 0 Returns : Standard deviation of the array elements (ignoring the Nan values) based on the set parameters. Code #1: Python3 # standard deviation import scipy import numpy as np arr1 = [1, 3, np.nan, 27] print("standard deviation using nanstd :", scipy.nanstd(arr1)) print("standard deviation without handling nan value :", scipy.std(arr1)) Output : standard deviation using nanstd : 11.813363431112899 standard deviation without handling nan value : nan Code #2: With multi-dimensional data Python3 # standard deviation from scipy import std from scipy import nanstd import numpy as np arr1 = [[1, 3, 27], [3, np.nan, 6], [np.nan, 6, 3], [3, 6, np.nan]] print("standard deviation is :", std(arr1)) print("standard deviation handling nan :", nanstd(arr1)) # using axis = 0 print("\nstandard deviation is with default axis = 0 : \n", std(arr1, axis = 0)) print("\nstandard deviation handling nan with default axis = 0 : \n", nanstd(arr1, axis = 0)) # using axis = 1 print("\nstandard deviation is with default axis = 1 : \n", std(arr1, axis = 1)) print("\nstandard deviation handling nan with default axis = 1 : \n", nanstd(arr1, axis = 1)) Output : standard deviation is : nan standard deviation handling nan : 7.455216087651669 standard deviation is with default axis =0 : [nan nan nan] standard deviation handling nan with default axis =0 : [ 0.94280904 1.41421356 10.67707825] standard deviation is with default axis =1 : [11.81336343 nan nan nan] standard deviation handling nan with default axis =1 : [11.81336343 1.5 1.5 1.5 ] Create Quiz Comment V vishal3096 Follow 0 Improve V vishal3096 Follow 0 Improve Article Tags : Python Python-scipy Python scipy-stats-functions Explore Python FundamentalsPython Introduction 2 min read Input and Output in Python 4 min read Python Variables 4 min read Python Operators 4 min read Python Keywords 2 min read Python Data Types 8 min read Conditional Statements in Python 3 min read Loops in Python - For, While and Nested Loops 5 min read Python Functions 5 min read Recursion in Python 4 min read Python Lambda Functions 5 min read Python Data StructuresPython String 5 min read Python Lists 4 min read Python Tuples 4 min read Python Dictionary 3 min read Python Sets 6 min read Python Arrays 7 min read List Comprehension in Python 4 min read Advanced PythonPython OOP Concepts 11 min read Python Exception Handling 5 min read File Handling in Python 4 min read Python Database Tutorial 4 min read Python MongoDB Tutorial 3 min read Python MySQL 9 min read Python Packages 10 min read Python Modules 3 min read Python DSA Libraries 15 min read List of Python GUI Library and Packages 3 min read Data Science with PythonNumPy Tutorial - Python Library 3 min read Pandas Tutorial 4 min read Matplotlib Tutorial 5 min read Python Seaborn Tutorial 3 min read StatsModel Library - Tutorial 3 min read Learning Model Building in Scikit-learn 6 min read TensorFlow Tutorial 2 min read PyTorch Tutorial 6 min read Web Development with PythonFlask Tutorial 8 min read Django Tutorial | Learn Django Framework 7 min read Django ORM - Inserting, Updating & Deleting Data 4 min read Templating With Jinja2 in Flask 6 min read Django Templates 5 min read Build a REST API using Flask - Python 3 min read Building a Simple API with Django REST Framework 3 min read Python PracticePython Quiz 1 min read Python Coding Practice 1 min read Python Interview Questions and Answers 15+ min read Like