Numpy MaskedArray.masked_equal() function | Python Last Updated : 27 Sep, 2019 Comments Improve Suggest changes Like Article Like Report In many circumstances, datasets can be incomplete or tainted by the presence of invalid data. For example, a sensor may have failed to record a data, or recorded an invalid value. The numpy.ma module provides a convenient way to address this issue, by introducing masked arrays.Masked arrays are arrays that may have missing or invalid entries. numpy.MaskedArray.masked_equal() function is used to mask an array where equal to a given value. Syntax : numpy.ma.masked_equal(arr, value, copy=True) Parameters: arr : [ndarray] Input array which we want to mask. value : [int] Element of masked array which we want to mask. copy : [bool] If True (default) make a copy of arr in the result. If False modify arr in place and return a view. Return : [ MaskedArray] The result of masking. Code #1 : Python3 # Python program explaining # numpy.MaskedArray.masked_equal() method # importing numpy as geek # and numpy.ma module as ma import numpy as geek import numpy.ma as ma # creating input array in_arr = geek.array([1, 2, 3, -1, 2]) print ("Input array : ", in_arr) # applying MaskedArray.masked_equal methods # to input array where value = 2 mask_arr = ma.masked_equal(in_arr, 2) print ("Masked array : ", mask_arr) Output: Input array : [ 1 2 3 -1 2] Masked array : [1 -- 3 -1 --] Code #2 : Python3 # Python program explaining # numpy.MaskedArray.masked_equal() method # importing numpy as geek # and numpy.ma module as ma import numpy as geek import numpy.ma as ma # creating input array in_arr = geek.array([2e8, 3e-5, -45.0, 2e5, 5e2]) print ("Input array : ", in_arr) # applying MaskedArray.masked_equal methods # to input array where value = 5e2 mask_arr = ma.masked_equal(in_arr, 5e2) print ("Masked array : ", mask_arr) Output: Input array : [ 2.0e+08 3.0e-05 -4.5e+01 2.0e+05 5.0e+02] Masked array : [200000000.0 3e-05 -45.0 200000.0 --] Comment More info J jana_sayantan Follow Improve Article Tags : Python Python-numpy Python numpy-arrayManipulation Explore Python FundamentalsPython Introduction 3 min read Input and Output in Python 4 min read Python Variables 5 min read Python Operators 5 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 7 min read Python Functions 5 min read Recursion in Python 6 min read Python Lambda Functions 5 min read Python Data StructuresPython String 5 min read Python Lists 5 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 2 min read Python MySQL 9 min read Python Packages 12 min read Python Modules 7 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 6 min read Matplotlib Tutorial 5 min read Python Seaborn Tutorial 15+ min read StatsModel Library- Tutorial 4 min read Learning Model Building in Scikit-learn 8 min read TensorFlow Tutorial 2 min read PyTorch Tutorial 7 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 7 min read Python | Build a REST API using Flask 3 min read How to Create a basic API using Django Rest Framework ? 4 min read Python PracticePython Quiz 3 min read Python Coding Practice 1 min read Python Interview Questions and Answers 15+ min read Like