NumPy

This is documentation for an old release of NumPy (version 1.18). Read this page in the documentation of the latest stable release (version 2.2).

Chebyshev Module (numpy.polynomial.chebyshev)

New in version 1.4.0.

This module provides a number of objects (mostly functions) useful for dealing with Chebyshev series, including a Chebyshev class that encapsulates the usual arithmetic operations. (General information on how this module represents and works with such polynomials is in the docstring for its “parent” sub-package, numpy.polynomial).

Chebyshev Class

Chebyshev(coef[, domain, window])

A Chebyshev series class.

Basics

chebval(x, c[, tensor])

Evaluate a Chebyshev series at points x.

chebval2d(x, y, c)

Evaluate a 2-D Chebyshev series at points (x, y).

chebval3d(x, y, z, c)

Evaluate a 3-D Chebyshev series at points (x, y, z).

chebgrid2d(x, y, c)

Evaluate a 2-D Chebyshev series on the Cartesian product of x and y.

chebgrid3d(x, y, z, c)

Evaluate a 3-D Chebyshev series on the Cartesian product of x, y, and z.

chebroots(c)

Compute the roots of a Chebyshev series.

chebfromroots(roots)

Generate a Chebyshev series with given roots.

Fitting

chebfit(x, y, deg[, rcond, full, w])

Least squares fit of Chebyshev series to data.

chebvander(x, deg)

Pseudo-Vandermonde matrix of given degree.

chebvander2d(x, y, deg)

Pseudo-Vandermonde matrix of given degrees.

chebvander3d(x, y, z, deg)

Pseudo-Vandermonde matrix of given degrees.

Calculus

chebder(c[, m, scl, axis])

Differentiate a Chebyshev series.

chebint(c[, m, k, lbnd, scl, axis])

Integrate a Chebyshev series.

Algebra

chebadd(c1, c2)

Add one Chebyshev series to another.

chebsub(c1, c2)

Subtract one Chebyshev series from another.

chebmul(c1, c2)

Multiply one Chebyshev series by another.

chebmulx(c)

Multiply a Chebyshev series by x.

chebdiv(c1, c2)

Divide one Chebyshev series by another.

chebpow(c, pow[, maxpower])

Raise a Chebyshev series to a power.

Quadrature

chebgauss(deg)

Gauss-Chebyshev quadrature.

chebweight(x)

The weight function of the Chebyshev polynomials.

Miscellaneous

chebcompanion(c)

Return the scaled companion matrix of c.

chebdomain

chebzero

chebone

chebx

chebtrim(c[, tol])

Remove “small” “trailing” coefficients from a polynomial.

chebline(off, scl)

Chebyshev series whose graph is a straight line.

cheb2poly(c)

Convert a Chebyshev series to a polynomial.

poly2cheb(pol)

Convert a polynomial to a Chebyshev series.