[Pkg-octave-commit] [SCM] octave-symbolic branch, master, updated. a718b53403d9f164f8c2a3df521385a01d28a11b

[watsma]

The following commit has been merged in the master branch:
commit 0e697c845a1228a5e0e45c7a9ac9a4bee049090f
Author: watsma <watsma at 416fae20-06d0-4450-9b69-c6c34d4b5f03>
Date:   Wed May 14 20:16:58 2003 +0000

    Initial commit. Returns symbolic polynomial given coefficients.
    
    
    git-svn-id: https://octave.svn.sourceforge.net/svnroot/octave/trunk/octave-forge/main/symbolic@936 416fae20-06d0-4450-9b69-c6c34d4b5f03

diff --git a/poly2sym.m b/poly2sym.m
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+## Copyright (C) 2003 Willem J. Atsma
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or
+## modify it under the terms of the GNU General Public
+## License as published by the Free Software Foundation;
+## either version 2, or (at your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied
+## warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+## PURPOSE.  See the GNU General Public License for more
+## details.
+##
+## You should have received a copy of the GNU General Public
+## License along with Octave; see the file COPYING.  If not,
+## write to the Free Software Foundation, 59 Temple Place -
+## Suite 330, Boston, MA 02111-1307, USA.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {} @var{p} = poly2sym (@var{c}, @var{x})
+## Creates a symbolic polynomial expression @var{p} with coefficients @var{c}.
+## If @var{p} is not specified, the free variable is set to sym("x"). @var{c}
+## may be a vector or a list/cell-array of symbols. @var{x} may be a symbolic
+## expression or a string.
+## The coefficients correspond to decreasing exponent of the free variable.
+##
+## Example:
+## @example
+## symbols
+## x=sym("x"); y=sym("y");
+## p = poly2sym ([2,5,-3]);         # p = 2*x^2+5*x-3
+## c = poly2sym (list(2*y,5,-3),x); # p = 2*y*x^2+5*x-3
+## @end example
+##
+## @end deftypefn
+## @seealso{sym2poly,polyval,roots}
+
+## Author: Willem J. Atsma <watsma(at)users.sf.net>
+## Created: April 2003
+
+function p = poly2sym(c,x)
+
+if exist("x")!=1
+	x = sym("x");
+endif
+
+N = length(c);
+
+if !iscell(c) & !is_list(c)
+	tmp = c;
+	c = list;
+	for i=1:N
+		c(i) = tmp(i);
+	endfor
+endif
+
+p = vpa(0);
+for i=1:N
+	if isnumeric(c{i})
+		p = p*x+vpa(c{i});
+	else
+		p = p*x+c{i};
+	endif
+endfor

-- 
octave-symbolic