Function
NumCosmoMathSpectralchebyshev_eval
Declaration [src]
gdouble
ncm_spectral_chebyshev_eval (
GArray* a,
gdouble t
)
Description [src]
Evaluates a Chebyshev expansion $f(t) = \sum_{k=0}^{N-1} a_k T_k(t)$ at t
using the Clenshaw recurrence, switching to the Reinsch modification near the
endpoints to avoid cancellation. The variable t should be in the interval
[-1, 1]. To evaluate at a point x in [a, b], use ncm_spectral_chebyshev_eval_x()
or first convert x to t using ncm_spectral_x_to_t(). See the
Spectral Methods page for details.