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## Copyright (C) 2007 Muthiah Annamalai <muthiah.annamalai@uta.edu>
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## This program is free software; you can redistribute it and/or modify it under
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## the terms of the GNU General Public License as published by the Free Software
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## Foundation; either version 3 of the License, or (at your option) any later
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## This program is distributed in the hope that it will be useful, but WITHOUT
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## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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## You should have received a copy of the GNU General Public License along with
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## this program; if not, see <http://www.gnu.org/licenses/>.
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## @deftypefn {Function File} {@var{coefs}=} legendrepoly (@var{order},@var{x})
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## Compute the coefficients of the Legendre polynomial, given the
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## @var{order}. We calculate the Legendre polynomial using the recurrence
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## relations, Pn+1(x) = inv(n+1)*((2n+1)*x*Pn(x) - nPn-1(x)).
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## If the value @var{x} is specified, the polynomial is also evaluated,
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## otherwise just the return the coefficients of the polynomial are returned.
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## This is NOT the generalized Legendre polynomial.
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function h = legendrepoly (order, val)
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if (nargin < 1 || nargin > 2)
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if (length(h_now) < (1+ord))
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y=zeros(1,(1+ord)-length(h_prev));
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h=((2*ord -1).*p1 -(ord -1).*p3)./(ord);