# numpy.polynomial.chebyshev.Chebyshev#

class numpy.polynomial.chebyshev.Chebyshev(coef, domain=None, window=None, symbol='x')[source]#

A Chebyshev series class.

The Chebyshev class provides the standard Python numerical methods ‘+’, ‘-’, ‘*’, ‘//’, ‘%’, ‘divmod’, ‘**’, and ‘()’ as well as the methods listed below.

Parameters:
coefarray_like

Chebyshev coefficients in order of increasing degree, i.e., `(1, 2, 3)` gives `1*T_0(x) + 2*T_1(x) + 3*T_2(x)`.

domain(2,) array_like, optional

Domain to use. The interval `[domain[0], domain[1]]` is mapped to the interval `[window[0], window[1]]` by shifting and scaling. The default value is [-1, 1].

window(2,) array_like, optional

Window, see `domain` for its use. The default value is [-1, 1].

New in version 1.6.0.

symbolstr, optional

Symbol used to represent the independent variable in string representations of the polynomial expression, e.g. for printing. The symbol must be a valid Python identifier. Default value is ‘x’.

New in version 1.24.

Attributes:
symbol

Methods

 `__call__`(arg) Call self as a function. `basis`(deg[, domain, window, symbol]) Series basis polynomial of degree deg. `cast`(series[, domain, window]) Convert series to series of this class. `convert`([domain, kind, window]) Convert series to a different kind and/or domain and/or window. Return a copy. `cutdeg`(deg) Truncate series to the given degree. The degree of the series. `deriv`([m]) Differentiate. `fit`(x, y, deg[, domain, rcond, full, w, ...]) Least squares fit to data. `fromroots`(roots[, domain, window, symbol]) Return series instance that has the specified roots. `has_samecoef`(other) Check if coefficients match. `has_samedomain`(other) Check if domains match. `has_sametype`(other) Check if types match. `has_samewindow`(other) Check if windows match. `identity`([domain, window, symbol]) Identity function. `integ`([m, k, lbnd]) Integrate. `interpolate`(func, deg[, domain, args]) Interpolate a function at the Chebyshev points of the first kind. `linspace`([n, domain]) Return x, y values at equally spaced points in domain. Return the mapping parameters. Return the roots of the series polynomial. `trim`([tol]) Remove trailing coefficients `truncate`(size) Truncate series to length size.