MaplePrimes - answers and comments on Question, Convert Trig to Legendre Polynomials

convert

gkokovidis — Tue, 09 Oct 2012 02:26:28 Z

See the help page for ?convert. The following link has more help as well.

http://www.maplesoft.com/support/help/Maple/view.aspx?path=convert%2fto_special_function

Regards,

Georgios Kokovidis

Dräger Medical

By OrthogonalExpansions package

Markiyan Hirnyk — Tue, 09 Oct 2012 19:00:23 Z

It is clear, that a transcendental function, say sin(x), cannot be represented as a sum of polynomials. Maybe, you mean the Legendre polynomial series expansions. In this case the ?OrthogonalExpansions package can be applied.

For example,
> with(OrthogonalExpansions):
> a := LegendreSeries(cos(x), x = 0 .. Pi, 3, 0, output = numeric);

> fnormal(a, 7);

Edit. Changed code.

Addition

Markiyan Hirnyk — Tue, 09 Oct 2012 22:55:13 Z

PS.