Subtract one polynomial from another.
Returns the difference of two polynomials c1 - c2. The arguments are sequences of coefficients from lowest order term to highest, i.e., [1,2,3] represents the polynomial
1 + 2*x + 3*x**2.
c1, c2 : array_like
1-D arrays of polynomial coefficients ordered from low to high.
out : ndarray
Of coefficients representing their difference.
>>> from numpy.polynomial import polynomial as P >>> c1 = (1,2,3) >>> c2 = (3,2,1) >>> P.polysub(c1,c2) array([-2., 0., 2.]) >>> P.polysub(c2,c1) # -P.polysub(c1,c2) array([ 2., 0., -2.])