numpy.ma.where() function - Python Last Updated : 05 May, 2020 Comments Improve Suggest changes Like Article Like Report numpy.ma.where() function return a masked array with elements from x or y, depending on condition. Syntax : numpy.ma.where(condition, x, y) Parameter : condition : [array_like, bool] Where True, yield x, otherwise yield y. x, y : [array_like, optional] Values from which to choose. x, y and condition need to be broadcastable to some shape. Return : [MaskedArray] An masked array with masked elements where the condition is masked, elements from x where condition is True, and elements from y elsewhere. Code #1 : Python3 # Python program explaining # numpy.ma.where() function # importing numpy as geek # and numpy.ma module as ma import numpy as geek import numpy.ma as ma x = geek.ma.array(geek.arange(4.).reshape(2, 2), mask =[[0, 1], [1, 0]]) gfg = geek.ma.where(x > 5, x, -3.1416) print (gfg) Output : [[-3.1416 --] [-- -3.1416]] Code #2 : Python3 # Python program explaining # numpy.ma.where() function # importing numpy as geek # and numpy.ma module as ma import numpy as geek import numpy.ma as ma x = geek.ma.array(geek.arange(9.).reshape(3, 3), mask =[[0, 1, 0], [1, 0, 1], [0, 1, 0]]) gfg = geek.ma.where(x > 5, x, -3.1416) print (gfg) Output : [[-3.1416 -- -3.1416] [-- -3.1416 --] [6.0 -- 8.0]] Comment More infoAdvertise with us Next Article Introduction to Machine Learning S sanjoy_62 Follow Improve Article Tags : Machine Learning Python-numpy python Python Numpy-Masked Array Practice Tags : Machine Learningpython Similar Reads Machine Learning Tutorial Machine learning is a branch of Artificial Intelligence that focuses on developing models and algorithms that let computers learn from data without being explicitly programmed for every task. 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