Numpy recarray.cumsum() function | Python Last Updated : 27 Sep, 2019 Comments Improve Suggest changes Like Article Like Report In numpy, arrays may have a data-types containing fields, analogous to columns in a spreadsheet. An example is [(a, int), (b, float)], where each entry in the array is a pair of (int, float). Normally, these attributes are accessed using dictionary lookups such as arr['a'] and arr['b']. Record arrays allow the fields to be accessed as members of the array, using arr.a and arr.b. numpy.recarray.cumsum() function returns the cumulative sum of array elements over a given axis. Syntax : numpy.recarray.cumsum(axis=None, dtype=None, out=None) Parameters: axis : Axis along which the cumulative sumis computed. The default is to compute the sum of the flattened array. dtype : Type of the returned array, as well as of the accumulator in which the elements are multiplied. 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. Return : A new array holding the result is returned unless out is specified, in which case it is returned. Code #1 : Python3 # Python program explaining # numpy.recarray.cumsum() method # importing numpy as geek import numpy as geek # creating input array with 2 different field in_arr = geek.array([[(5.0, 2), (3.0, -4), (6.0, 9)], [(9.0, 1), (5.0, 4), (-12.0, -7)]], dtype =[('a', float), ('b', int)]) print ("Input array : ", in_arr) # convert it to a record array, # using arr.view(np.recarray) rec_arr = in_arr.view(geek.recarray) print("Record array of float: ", rec_arr.a) print("Record array of int: ", rec_arr.b) # applying recarray.cumsum methods # to float record array along axis 1 out_arr = rec_arr.a.cumsum( axis = 1) print ("Output array along axis 1: ", out_arr) # applying recarray.cumsum methods # to int record array along default axis out_arr = rec_arr.b.cumsum() print ("Output array along default axis : ", out_arr) Output: Input array : [[( 5., 2) ( 3., -4) ( 6., 9)] [( 9., 1) ( 5., 4) (-12., -7)]] Record array of float: [[ 5. 3. 6.] [ 9. 5. -12.]] Record array of int: [[ 2 -4 9] [ 1 4 -7]] Output array along axis 1: [[ 5. 8. 14.] [ 9. 14. 2.]] Output array along default axis : [ 2 -2 7 8 12 5] Create Quiz Comment J jana_sayantan Follow 0 Improve J jana_sayantan 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