numpy.logaddexp2() in Python Last Updated : 28 Nov, 2018 Comments Improve Suggest changes Like Article Like Report numpy.logaddexp2() function is used to calculate Logarithm of the sum of exponentiations of the inputs in base-2. This function is useful in machine learning when the calculated probabilities of events may be so small as to exceed the range of normal floating point numbers. In such cases, the base-2 logarithm of the calculated probability can be used instead. This function allows adding probabilities stored in such a fashion. It Calculates log2(2**x1 + 2**x2). Syntax : numpy.logaddexp2(arr1, arr2, /, out=None, *, where=True, casting='same_kind', order='K', dtype=None, ufunc ‘logaddexp’) Parameters : arr1 : [array_like] Input array. arr2 : [array_like] Input array. out : [ndarray, optional] A location into which the result is stored. -> If provided, it must have a shape that the inputs broadcast to. -> If not provided or None, a freshly-allocated array is returned. where : [array_like, optional] True value means to calculate the universal functions(ufunc) at that position, False value means to leave the value in the output alone. **kwargs : allows you to pass keyword variable length of argument to a function. It is used when we want to handle named argument in a function. Return : [ndarray or scalar] It returns Base-2 logarithm of 2**x1 + 2**x2. This is a scalar if both arr1 and arr2 are scalars. Code #1 : Python3 # Python3 code demonstrate logaddexp2() function # importing numpy import numpy as geek in_num1 = 2 in_num2 = 3 print ("Input number1 : ", in_num1) print ("Input number2 : ", in_num2) out_num = geek.logaddexp2(in_num1, in_num2) print ("Output number : ", out_num) Output : Input number1 : 2 Input number2 : 3 Output number : 3.58496250072 Code #2 : Python3 # Python3 code demonstrate logaddexp2() function # importing numpy import numpy as geek in_arr1 = [2, 3, 8] in_arr2 = [1, 2, 3] print ("Input array1 : ", in_arr1) print ("Input array2 : ", in_arr2) out_arr = geek.logaddexp2(in_arr1, in_arr2) print ("Output array : ", out_arr) Output : Input array1 : [2, 3, 8] Input array2 : [1, 2, 3] Output array : [ 2.5849625 3.5849625 8.04439412] Comment More info J jana_sayantan Follow Improve Article Tags : Python Python-numpy Python numpy-Mathematical Function 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 7 min read Conditional Statements in Python 3 min read Loops in Python - For, While and Nested Loops 6 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 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