update packages

[CreaPhase.git] / octave_packages / m / general / private / __splinen__.m

diff --git a/octave_packages/m/general/private/__splinen__.m b/octave_packages/m/general/private/__splinen__.m
new file mode 100644 (file)
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+++ b/octave_packages/m/general/private/__splinen__.m
@@ -0,0 +1,49 @@
+## Copyright (C) 2007-2012 David Bateman
+##
+## 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/>.
+
+## Undocumented internal function.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{yi} =} __splinen__ (@var{x}, @var{y}, @var{xi})
+## Undocumented internal function.
+## @end deftypefn
+
+## FIXME: Allow arbitrary grids..
+
+function yi = __splinen__ (x, y, xi, extrapval, f)
+  if (nargin != 5)
+    error ("__splinen__: Incorrect number of arguments");
+  endif
+  ## ND isvector function.
+  isvec = @(x) numel (x) == length (x);
+  if (!iscell (x) || length(x) < ndims(y) || any (! cellfun (isvec, x))
+      || !iscell (xi) || length(xi) < ndims(y) || any (! cellfun (isvec, xi)))
+    error ("__splinen__: %s: non gridded data or dimensions inconsistent", f);
+  endif
+  yi = y;
+  for i = length(x):-1:1
+    yi = permute (spline (x{i}, yi, xi{i}(:)), [length(x),1:length(x)-1]);
+  endfor
+
+  [xi{:}] = ndgrid (cellfun (@(x) x(:), xi, "uniformoutput", false){:});
+  idx = zeros (size(xi{1}));
+  for i = 1 : length(x)
+    idx |= xi{i} < min (x{i}(:)) | xi{i} > max (x{i}(:));
+  endfor
+  yi(idx) = extrapval;
+endfunction