update packages

[CreaPhase.git] / octave_packages / m / polynomial / polyint.m

diff --git a/octave_packages/m/polynomial/polyint.m b/octave_packages/m/polynomial/polyint.m
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+## Copyright (C) 1996-2012 John W. Eaton
+##
+## 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 3 of the License, 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, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {} polyint (@var{p})
+## @deftypefnx {Function File} {} polyint (@var{p}, @var{k})
+## Return the coefficients of the integral of the polynomial whose
+## coefficients are represented by the vector @var{p}.  The variable
+## @var{k} is the constant of integration, which by default is set to zero.
+## @seealso{polyder, polyval}
+## @end deftypefn
+
+## Author: Tony Richardson <arichard@stark.cc.oh.us>
+## Created: June 1994
+## Adapted-By: jwe
+
+function retval = polyint (p, k)
+
+  if (nargin < 1 || nargin > 2)
+    print_usage ();
+  endif
+
+  if (nargin == 1)
+    k = 0;
+  elseif (! isscalar (k))
+    error ("polyint: the constant of integration must be a scalar");
+  endif
+
+  if (! (isvector (p) || isempty (p)))
+    error ("polyint: argument must be a vector");
+  endif
+
+  lp = length (p);
+
+  if (lp == 0)
+    retval = [];
+    return;
+  endif
+
+  if (rows (p) > 1)
+    ## Convert to column vector
+    p = p.';
+  endif
+
+  retval = [(p ./ [lp:-1:1]), k];
+
+endfunction
+
+%!test
+%! A = [3, 2, 1];
+%! assert (polyint(A),polyint(A,0));
+%! assert (polyint(A),polyint(A'));
+%! assert (polyint(A),[1, 1, 1, 0]);
+%! assert (polyint(A,1),ones(1,4));
+
+%!test
+%! A = ones(1,8);
+%! B = [length(A):-1:1];
+%! assert (polyint(A),[1./B, 0]);
+
+%!error polyint()
+%!error polyint(ones(2,2))