update packages

[CreaPhase.git] / octave_packages / m / geometry / griddata3.m

diff --git a/octave_packages/m/geometry/griddata3.m b/octave_packages/m/geometry/griddata3.m
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+## 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/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{vi} =} griddata3 (@var{x}, @var{y}, @var{z}, @var{v}, @var{xi}, @var{yi}, @var{zi}, @var{method}, @var{options})
+##
+## Generate a regular mesh from irregular data using interpolation.
+## The function is defined by @code{@var{v} = f (@var{x}, @var{y}, @var{z})}.
+## The interpolation points are specified by @var{xi}, @var{yi}, @var{zi}.
+##
+## The interpolation method can be @code{"nearest"} or @code{"linear"}.
+## If method is omitted it defaults to @code{"linear"}.
+## @seealso{griddata, griddatan, delaunayn}
+## @end deftypefn
+
+## Author: David Bateman <dbateman@free.fr>
+
+function vi = griddata3 (x, y, z, v, xi, yi, zi, method, varargin)
+
+  if (nargin < 7)
+    print_usage ();
+  endif
+
+  if (!all (size (x) == size (y) & size (x) == size(z) & size(x) == size (v)))
+    error ("griddata3: X, Y, Z, and V must be vectors of same length");
+  endif
+
+  ## meshgrid xi, yi and zi if they are vectors unless they
+  ## are vectors of the same length
+  if (isvector (xi) && isvector (yi) && isvector (zi)
+      && (numel (xi) != numel (yi) || numel (xi) != numel (zi)))
+    [xi, yi, zi] = meshgrid (xi, yi, zi);
+  endif
+
+  if (any (size(xi) != size(yi)) || any (size(xi) != size(zi)))
+    error ("griddata3: XI, YI and ZI must be vectors or matrices of same size");
+  endif
+
+  vi = griddatan ([x(:), y(:), z(:)], v(:), [xi(:), yi(:), zi(:)], varargin{:});
+  vi = reshape (vi, size (xi));
+
+endfunction
+
+
+%!testif HAVE_QHULL
+%! old_state = rand ("state");
+%! restore_state = onCleanup (@() rand ("state", old_state));
+%! rand ("state", 0);
+%! x = 2 * rand (1000, 1) - 1;
+%! y = 2 * rand (1000, 1) - 1;
+%! z = 2 * rand (1000, 1) - 1;
+%! v = x.^2 + y.^2 + z.^2;
+%! [xi, yi, zi] = meshgrid (-0.8:0.2:0.8);
+%! vi = griddata3 (x, y, z, v, xi, yi, zi, 'linear');
+%! vv = vi - xi.^2 - yi.^2 - zi.^2;
+%! assert (max (abs (vv(:))), 0, 0.1);
+
+%!testif HAVE_QHULL
+%! old_state = rand ("state");
+%! restore_state = onCleanup (@() rand ("state", old_state));
+%! rand ("state", 0);
+%! x = 2 * rand (1000, 1) - 1;
+%! y = 2 * rand (1000, 1) - 1;
+%! z = 2 * rand (1000, 1) - 1;
+%! v = x.^2 + y.^2 + z.^2;
+%! [xi, yi, zi] = meshgrid (-0.8:0.2:0.8);
+%! vi = griddata3 (x, y, z, v, xi, yi, zi, 'nearest');
+%! vv = vi - xi.^2 - yi.^2 - zi.^2;
+%! assert (max (abs (vv(:))), 0, 0.1)