numpy.polysub

numpy.polysub(a1, a2)

Difference (subtraction) of two polynomials.

Given two polynomials a1 and a2, returns a1 - a2. a1 and a2 can be either array_like sequences of the polynomials’ coefficients (including coefficients equal to zero), or poly1d objects.

Parameters:

a1, a2 : array_like or poly1d

Minuend and subtrahend polynomials, respectively.

Returns:

out : ndarray or poly1d

Array or poly1d object of the difference polynomial’s coefficients.

See also

polyval, polydiv, polymul, polyadd

Examples

(2 x^2 + 10 x - 2) - (3 x^2 + 10 x -4) = (-x^2 + 2)

>>> np.polysub([2, 10, -2], [3, 10, -4])
array([-1,  0,  2])