numpy.polynomial.chebyshev.poly2cheb — NumPy v1.15 Manual (original) (raw)
numpy.polynomial.chebyshev. poly2cheb(pol)[source]¶
Convert a polynomial to a Chebyshev series.
Convert an array representing the coefficients of a polynomial (relative to the “standard” basis) ordered from lowest degree to highest, to an array of the coefficients of the equivalent Chebyshev series, ordered from lowest to highest degree.
| Parameters: | pol : array_like 1-D array containing the polynomial coefficients |
|---|---|
| Returns: | c : ndarray 1-D array containing the coefficients of the equivalent Chebyshev series. |
Notes
The easy way to do conversions between polynomial basis sets is to use the convert method of a class instance.
Examples
from numpy import polynomial as P p = P.Polynomial(range(4)) p Polynomial([ 0., 1., 2., 3.], domain=[-1, 1], window=[-1, 1]) c = p.convert(kind=P.Chebyshev) c Chebyshev([ 1. , 3.25, 1. , 0.75], domain=[-1, 1], window=[-1, 1]) P.poly2cheb(range(4)) array([ 1. , 3.25, 1. , 0.75])