SciPy

scipy.special.eval_chebyt

scipy.special.eval_chebyt(n, x, out=None) = <ufunc 'eval_chebyt'>

Evaluate Chebyshev polynomial of the first kind at a point.

The Chebyshev polynomials of the first kind can be defined via the Gauss hypergeometric function \({}_2F_1\) as

\[T_n(x) = {}_2F_1(n, -n; 1/2; (1 - x)/2).\]

When \(n\) is an integer the result is a polynomial of degree \(n\).

Parameters:

n : array_like

Degree of the polynomial. If not an integer, the result is determined via the relation to the Gauss hypergeometric function.

x : array_like

Points at which to evaluate the Chebyshev polynomial

Returns:

T : ndarray

Values of the Chebyshev polynomial

See also

roots_chebyt
roots and quadrature weights of Chebyshev polynomials of the first kind
chebyu
Chebychev polynomial object
eval_chebyu
evaluate Chebyshev polynomials of the second kind
hyp2f1
Gauss hypergeometric function
numpy.polynomial.chebyshev.Chebyshev
Chebyshev series

Notes

This routine is numerically stable for x in [-1, 1] at least up to order 10000.