numpy.polynomial.chebyshev.chebdiv — NumPy v1.11 Manual (original) (raw)

numpy.polynomial.chebyshev.chebdiv(c1, c2)[source]

Divide one Chebyshev series by another.

Returns the quotient-with-remainder of two Chebyshev series_c1_ / c2. The arguments are sequences of coefficients from lowest order “term” to highest, e.g., [1,2,3] represents the seriesT_0 + 2*T_1 + 3*T_2.

Parameters: c1, c2 : array_like 1-D arrays of Chebyshev series coefficients ordered from low to high.
Returns: [quo, rem] : ndarrays Of Chebyshev series coefficients representing the quotient and remainder.

Notes

In general, the (polynomial) division of one C-series by another results in quotient and remainder terms that are not in the Chebyshev polynomial basis set. Thus, to express these results as C-series, it is typically necessary to “reproject” the results onto said basis set, which typically produces “unintuitive” (but correct) results; see Examples section below.

Examples

from numpy.polynomial import chebyshev as C c1 = (1,2,3) c2 = (3,2,1) C.chebdiv(c1,c2) # quotient "intuitive," remainder not (array([ 3.]), array([-8., -4.])) c2 = (0,1,2,3) C.chebdiv(c2,c1) # neither "intuitive" (array([ 0., 2.]), array([-2., -4.]))