SciPy

This is documentation for an old release of NumPy (version 1.17). Read this page in the documentation of the latest stable release (version 2.2).

Legendre Module (numpy.polynomial.legendre)

New in version 1.6.0.

This module provides a number of objects (mostly functions) useful for dealing with Legendre series, including a Legendre 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).

Legendre Class

Legendre(coef[, domain, window]) A Legendre series class.

Basics

legval(x, c[, tensor]) Evaluate a Legendre series at points x.
legval2d(x, y, c) Evaluate a 2-D Legendre series at points (x, y).
legval3d(x, y, z, c) Evaluate a 3-D Legendre series at points (x, y, z).
leggrid2d(x, y, c) Evaluate a 2-D Legendre series on the Cartesian product of x and y.
leggrid3d(x, y, z, c) Evaluate a 3-D Legendre series on the Cartesian product of x, y, and z.
legroots(c) Compute the roots of a Legendre series.
legfromroots(roots) Generate a Legendre series with given roots.

Fitting

legfit(x, y, deg[, rcond, full, w]) Least squares fit of Legendre series to data.
legvander(x, deg) Pseudo-Vandermonde matrix of given degree.
legvander2d(x, y, deg) Pseudo-Vandermonde matrix of given degrees.
legvander3d(x, y, z, deg) Pseudo-Vandermonde matrix of given degrees.

Calculus

legder(c[, m, scl, axis]) Differentiate a Legendre series.
legint(c[, m, k, lbnd, scl, axis]) Integrate a Legendre series.

Algebra

legadd(c1, c2) Add one Legendre series to another.
legsub(c1, c2) Subtract one Legendre series from another.
legmul(c1, c2) Multiply one Legendre series by another.
legmulx(c) Multiply a Legendre series by x.
legdiv(c1, c2) Divide one Legendre series by another.
legpow(c, pow[, maxpower]) Raise a Legendre series to a power.

Quadrature

leggauss(deg) Gauss-Legendre quadrature.
legweight(x) Weight function of the Legendre polynomials.

Miscellaneous

legcompanion(c) Return the scaled companion matrix of c.
legdomain
legzero
legone
legx
legtrim(c[, tol]) Remove “small” “trailing” coefficients from a polynomial.
legline(off, scl) Legendre series whose graph is a straight line.
leg2poly(c) Convert a Legendre series to a polynomial.
poly2leg(pol) Convert a polynomial to a Legendre series.