  # numpy.poly () in Python

NumPy | Python Methods and Functions

` numpy.poly (seq) `: given a sequence of roots of a polynomial, this function returns the coefficient of the polynomial.

Parameters:
Seq: sequence of roots of the polynomial roots, or a matrix of roots.

Return: 1D array having coefficients of the polynomial from the highest degree to the lowest one.
c  * x ** (N) + c  * x ** (N-1) + ... + c [N-1 ] * x + c [N] where c  always equals 1.

 ` # Python code explaining ` ` # numpy.poly () `   ` # import libraries ` ` import ` ` numpy as np `   ` # Give cor nor ` ` seq_1 ` ` = ` ` ( 2 , 1 , 0 ) `` a = np.poly (seq_1) print ( "Coefficients of the polynomial:" , a)   # Plotting a polynomial p1 = np.poly1d (a) print ( " Above polynomial = " , p1)  `

Output:

Coefficients of the polynomial: [1. -3. 2. 0.] Above polynomial = 3 2 1 x - 3 x + 2 x

Code # 2:

 ` # Python code explaining ` ` # numpy.poly () ` ` `  ` # importing libraries ` ` import ` ` numpy as np ` ` `  ` # Giving roots ` ` seq_2 ` ` = ` ` (` ` 2 ` `, ` ` 1 ` `, ` ` 0 ` `, ` ` 2 ` `, ` ` 4 ` `, ` ` 2 ` `) ` ` b ` ` = ` ` np.poly (seq_2) ` ` print ` ` (` `" Coefficients of the polynomial: "` `, b) ` ` `  ` # Building a polynomial ` ` p2 ` ` = np.poly1d (b) `` print ( "Above polynomial =" , p2) `

Output:

` Coefficients of the polynomial: [1. -11. 46. ​​-92. 88.-32. 0.] Above polynomial = 6 5 4 3 2 1 x - 11 x + 46 x - 92 x + 88 x - 32 x `