numpy.polymul()

numpy.polymul(a1, a2) [source]

Find the product of two polynomials.

Finds the polynomial resulting from the multiplication of the two input polynomials. Each input must be either a poly1d object or a 1D sequence of polynomial coefficients, from highest to lowest degree.

Parameters:

Parameters:	a1, a2 : array_like or poly1d object Input polynomials.
Returns:	out : ndarray or poly1d object The polynomial resulting from the multiplication of the inputs. If either inputs is a poly1d object, then the output is also a poly1d object. Otherwise, it is a 1D array of polynomial coefficients from highest to lowest degree.

a1, a2 : array_like or poly1d object

Input polynomials.

Returns:

out : ndarray or poly1d object

The polynomial resulting from the multiplication of the inputs. If either inputs is a poly1d object, then the output is also a poly1d object. Otherwise, it is a 1D array of polynomial coefficients from highest to lowest degree.

Examples

>>> np.polymul([1, 2, 3], [9, 5, 1])
array([ 9, 23, 38, 17,  3])

Using poly1d objects:

>>> p1 = np.poly1d([1, 2, 3])
>>> p2 = np.poly1d([9, 5, 1])
>>> print(p1)
   2
1 x + 2 x + 3
>>> print(p2)
   2
9 x + 5 x + 1
>>> print(np.polymul(p1, p2))
   4      3      2
9 x + 23 x + 38 x + 17 x + 3

Links:

https://docs.scipy.org/doc/numpy-1.11.0/reference/generated/numpy.polymul.html

doc_NumPy

2025-01-10 15:47:30

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