### Table Of Contents

- Chebyshev Module (`numpy.polynomial.chebyshev`)
  - Chebyshev Class
  - Basics
  - Fitting
  - Calculus
  - Algebra
  - Quadrature
  - Miscellaneous

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numpy.polynomial.chebyshev.Chebyshev

# 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.