--- /dev/null
+## Copyright (C) 2000 Kai Habel
+##
+## This program 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 of the License, or
+## (at your option) any later version.
+##
+## This program 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 this program; If not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{pp} = } csapi (@var{x}, @var{y})
+## @deftypefnx {Function File} {@var{yi} = } csapi (@var{x}, @var{y}, @var{xi})
+## cubic spline interpolation
+##
+## @seealso{ppval, spline, csape}
+## @end deftypefn
+
+## Author: Kai Habel <kai.habel@gmx.de>
+## Date: 3. dec 2000
+
+function ret = csapi (x, y, xi)
+
+ ret = csape(x,y,'not-a-knot');
+
+ if (nargin == 3)
+ ret = ppval(ret,xi);
+ endif
+
+endfunction