numpy.in1d() function in Python Last Updated : 17 May, 2020 Comments Improve Suggest changes Like Article Like Report numpy.in1d() function test whether each element of a 1-D array is also present in a second array and return a boolean array the same length as arr1 that is True where an element of arr1 is in arr2 and False otherwise. Syntax : numpy.in1d(arr1, arr2, assume_unique = False, invert = False) Parameters : arr1 : [array_like] Input array. arr2 : [array_like] The values against which to test each value of arr1. assume_unique : [bool, optional] If True, the input arrays are both assumed to be unique, which can speed up the calculation. Default is False. invert : [bool, optional] If True, the values in the returned array are inverted. Default is False. Return : [ndarray, bool] The values arr1[in1d] are in arr2. Code #1 : Python3 # Python program explaining # numpy.in1d() function # importing numpy as geek import numpy as geek arr1 = geek.array([0, 1, 2, 3, 0, 4, 5]) arr2 = [0, 2, 5] gfg = geek.in1d(arr1, arr2) print (gfg) Output : [ True False True False True False True] Code #2 : Python3 # Python program explaining # numpy.in1d() function # importing numpy as geek import numpy as geek arr1 = geek.array([0, 1, 2, 3, 0, 4, 5]) arr2 = [0, 2, 5] gfg = geek.in1d(arr1, arr2, invert = True) print (gfg) Output : [False True False True False True False] Create Quiz Comment S sanjoy_62 Follow 0 Improve S sanjoy_62 Follow 0 Improve Article Tags : Python Python-numpy Python numpy-arrayManipulation 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