# numpy.polyval() in Python

numpy.polyval(p, x) method evaluates a polynomial at specific values.

If ‘N’ is the length of polynomial ‘p’, then this function returns the value `Parameters : `
p : [array_like or poly1D] polynomial coefficients are given in decreasing order of powers. If the second parameter (root) is set to True then array values are the roots of the polynomial equation.
For example : poly1d(3, 2, 6) = 3x2 + 2x + 6

x : [array_like or poly1D] A number, an array of numbers, for evaluating ‘p’.

`Return:` Evaluated value of polynomial.

Code : Python code explaining polyval()

 `# Python code explaining  ` `# numpy.polyval() ` `   `  `# importing libraries ` `import` `numpy as np ` `import` `pandas as pd ` `   `  `# Constructing polynomial  ` `p1 ``=` `np.poly1d([``1``, ``2``])  ` `p2 ``=` `np.poly1d([``4``, ``9``, ``5``, ``4``])  ` `   `  `print` `(``"P1 : "``, p1)  ` `print` `(``"\n p2 : \n"``, p2)  ` `# Solve for x = 2  ` `print` `(``"\n\np1 at x = 2 : "``, p1(``2``))  ` `print` `(``"p2 at x = 2 : "``, p2(``2``))  ` `a ``=` `np.polyval([``1``, ``2``], ``2``) ` `b ``=` `np.polyval([``4``, ``9``, ``5``, ``4``], ``2``) ` ` `  `print` `(``"\n\nUsing polyval"``) ` `print` `(``"p1 at x = 2 : "``, a)  ` `print` `(``"p2 at x = 2 : "``, b)  ` ` `  `c ``=` `np.polyval(np.poly1d([``4``, ``9``, ``5``, ``4``]), np.poly1d(``2``)) ` `print` `(``"\nc : "``, c) ` My Personal Notes arrow_drop_up If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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