Python | Numpy np.polyroots() method Last Updated : 31 Dec, 2019 Comments Improve Suggest changes Like Article Like Report np.polyroots() method is used to compute the roots of a polynomial series.Return the roots of the polynomial. Syntax : np.polyroots(c) Parameters: c :[array_like] 1-D arrays of polynomial series coefficients. Return : [ndarray] Array of the roots of the series. If all the roots are real, then out is also real, otherwise it is complex. Code #1 : Python3 # Python program explaining # numpy.polyroots() method # importing numpy as np # and numpy.polynomial.polynomial module as geek import numpy as np import numpy.polynomial.polynomial as geek # Input polynomial series coefficients s = (2, 4, 8) # using np.polyroots() method res = geek.polyroots(s) # Resulting polynomial series coefficient print (res) Output: [-0.25-0.4330127j -0.25+0.4330127j] Code #2 : Python3 # Python program explaining # numpy.polyroot() method # importing numpy as np # and numpy.polynomial.polynomial module as geek import numpy as np import numpy.polynomial.polynomial as geek # polynomial series coefficients s = (1, 2, 3, 4, 5) # using np.polyroots() method res = geek.polyroots(s) # Resulting polynomial series print (res) Output: [-0.53783227-0.35828469j -0.53783227+0.35828469j 0.13783227-0.67815439j 0.13783227+0.67815439j] Comment More infoAdvertise with us Next Article Python | Numpy np.polyroots() method jana_sayantan Follow Improve Article Tags : Python Python-numpy Python numpy-Mathematical Function Practice Tags : python Similar Reads Python | Numpy np.polyfromroots() method np.polyfromroots() method is used to generate a polynomial series with given roots. 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