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# numpy.poly() in Python

The numpy.poly() function in the Sequence of roots of the polynomial returns the coefficient of the polynomial.

Syntax :numpy.poly(seq)

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[0] * x**(N) + c[1] * x**(N-1) + … + c[N-1] * x + c[N] where c[0] always equals 1.

 `# Python code explaining  ``# numpy.poly() ``     ` `# importing libraries ``import` `numpy as np ``   ` `# Giving the roots ``seq_1 ``=` `(``2``, ``1``, ``0``)``a ``=` `np.poly(seq_1)``print` `(``"Coefficients of the polynomial: "``, a)`` ` `# Constructing polynomial  ``p1 ``=` `np.poly1d(a)``print` `(``"\nAbove polynomial = \n"``, 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 the roots``seq_2 ``=` `(``2``, ``1``, ``0``, ``2``, ``4``, ``2``)``b ``=` `np.poly(seq_2)``print` `(``"Coefficients of the polynomial: "``, b)`` ` `# Constructing polynomial  ``p2 ``=` `np.poly1d(b)``print` `(``"\nAbove polynomial = \n"``, 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
```