1 ## Copyright (C) 2000 Kai Habel
3 ## This program is free software; you can redistribute it and/or modify
4 ## it under the terms of the GNU General Public License as published by
5 ## the Free Software Foundation; either version 2 of the License, or
6 ## (at your option) any later version.
8 ## This program is distributed in the hope that it will be useful,
9 ## but WITHOUT ANY WARRANTY; without even the implied warranty of
10 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 ## GNU General Public License for more details.
13 ## You should have received a copy of the GNU General Public License
14 ## along with this program; If not, see <http://www.gnu.org/licenses/>.
17 ## @deftypefn {Function File} { } fnder (@var{pp}, @var{order})
18 ## differentiate the spline in pp-form
23 ## Author: Kai Habel <kai.habel@gmx.de>
26 function dpp = fnder (pp, o)
28 if (nargin < 1 || nargin > 2)
29 usage ("fnder (pp [, order])");
35 [X, P, N, K, D] = unmkpp (pp);
40 #pp.P = polyder (pp.P); matrix capable polyder is needed.
41 P = P(:, 1:c - 1) .* kron ((c - 1):- 1:1, ones (r,1));