1 ## Copyright (C) 2007 Muthiah Annamalai <muthiah.annamalai@mavs.uta.edu>
3 ## This program is free software; you can redistribute it and/or modify it under
4 ## the terms of the GNU General Public License as published by the Free Software
5 ## Foundation; either version 3 of the License, or (at your option) any later
8 ## This program is distributed in the hope that it will be useful, but WITHOUT
9 ## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 ## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
13 ## You should have received a copy of the GNU General Public License along with
14 ## this program; if not, see <http://www.gnu.org/licenses/>.
17 ## @deftypefn {Function File} {@var{coefs}=} chebyshevpoly (@var{kind},@var{order},@var{x})
19 ## Compute the coefficients of the Chebyshev polynomial, given the
20 ## @var{order}. We calculate the Chebyshev polynomial using the recurrence
21 ## relations, Tn+1(x) = (2*x*Tn(x) - Tn-1(x)). The @var{kind} can set to
22 ## compute the first or second kind chebyshev polynomial.
24 ## If the value @var{x} is specified, the polynomial is also evaluated,
25 ## otherwise just the return the coefficients of the polynomial are returned.
27 ## This is NOT the generalized Chebyshev polynomial.
31 function h=chebyshevpoly(kind,order,val)
32 if nargin < 2, print_usage, endif
40 error('unknown kind');
51 if (length(h_now) < (1+ord))
54 y=zeros(1,(1+ord)-length(h_prev));