Mercurial > octave-antonio
view scripts/general/divergence.m @ 20158:7503499a252b stable
doc: Update docstrings to have one sentence summary as first line.
Update scripts in audio, elfun, general, geometry, and image directories.
* scripts/audio/@audioplayer/__get_properties__.m,
scripts/audio/@audioplayer/audioplayer.m, scripts/audio/@audioplayer/get.m,
scripts/audio/@audioplayer/isplaying.m, scripts/audio/@audioplayer/play.m,
scripts/audio/@audioplayer/playblocking.m, scripts/audio/@audioplayer/set.m,
scripts/audio/@audioplayer/subsasgn.m, scripts/audio/@audioplayer/subsref.m,
scripts/audio/@audiorecorder/audiorecorder.m,
scripts/audio/@audiorecorder/get.m,
scripts/audio/@audiorecorder/getaudiodata.m,
scripts/audio/@audiorecorder/getplayer.m,
scripts/audio/@audiorecorder/isrecording.m,
scripts/audio/@audiorecorder/play.m, scripts/audio/@audiorecorder/record.m,
scripts/audio/@audiorecorder/recordblocking.m,
scripts/audio/@audiorecorder/set.m, scripts/audio/@audiorecorder/stop.m,
scripts/audio/@audiorecorder/subsasgn.m,
scripts/audio/@audiorecorder/subsref.m, scripts/audio/lin2mu.m,
scripts/audio/mu2lin.m, scripts/audio/record.m, scripts/audio/sound.m,
scripts/audio/soundsc.m, scripts/audio/wavread.m, scripts/audio/wavwrite.m,
scripts/elfun/cosd.m, scripts/elfun/sind.m, scripts/elfun/tand.m,
scripts/general/accumarray.m, scripts/general/accumdim.m,
scripts/general/bitcmp.m, scripts/general/bitget.m, scripts/general/bitset.m,
scripts/general/blkdiag.m, scripts/general/cart2pol.m,
scripts/general/cart2sph.m, scripts/general/cell2mat.m,
scripts/general/celldisp.m, scripts/general/chop.m,
scripts/general/circshift.m, scripts/general/common_size.m,
scripts/general/cplxpair.m, scripts/general/cumtrapz.m,
scripts/general/dblquad.m, scripts/general/deal.m, scripts/general/del2.m,
scripts/general/display.m, scripts/general/divergence.m,
scripts/general/fieldnames.m, scripts/general/flip.m,
scripts/general/flipdim.m, scripts/general/fliplr.m, scripts/general/flipud.m,
scripts/general/gradient.m, scripts/general/interp3.m,
scripts/general/interpft.m, scripts/general/interpn.m,
scripts/general/loadobj.m, scripts/general/logspace.m,
scripts/general/methods.m, scripts/general/nargchk.m,
scripts/general/narginchk.m, scripts/general/nargoutchk.m,
scripts/general/nextpow2.m, scripts/general/nthargout.m,
scripts/general/num2str.m, scripts/general/pol2cart.m,
scripts/general/polyarea.m, scripts/general/postpad.m,
scripts/general/prepad.m, scripts/general/profile.m, scripts/general/quadgk.m,
scripts/general/quadl.m, scripts/general/quadv.m, scripts/general/randi.m,
scripts/general/rat.m, scripts/general/repmat.m, scripts/general/rot90.m,
scripts/general/rotdim.m, scripts/general/saveobj.m, scripts/general/shift.m,
scripts/general/shiftdim.m, scripts/general/sortrows.m,
scripts/general/sph2cart.m, scripts/general/structfun.m,
scripts/general/subsindex.m, scripts/general/trapz.m,
scripts/general/triplequad.m, scripts/geometry/delaunayn.m,
scripts/geometry/dsearch.m, scripts/geometry/dsearchn.m,
scripts/geometry/griddata.m, scripts/geometry/griddata3.m,
scripts/geometry/griddatan.m, scripts/geometry/inpolygon.m,
scripts/geometry/rectint.m, scripts/geometry/tsearchn.m,
scripts/geometry/voronoi.m, scripts/geometry/voronoin.m,
scripts/help/__unimplemented__.m, scripts/help/doc.m,
scripts/help/doc_cache_create.m, scripts/help/get_first_help_sentence.m,
scripts/help/help.m, scripts/help/lookfor.m, scripts/help/print_usage.m,
scripts/help/type.m, scripts/help/which.m, scripts/image/autumn.m,
scripts/image/bone.m, scripts/image/brighten.m, scripts/image/cmpermute.m,
scripts/image/colorcube.m, scripts/image/contrast.m, scripts/image/cool.m,
scripts/image/copper.m, scripts/image/cubehelix.m, scripts/image/flag.m,
scripts/image/gmap40.m, scripts/image/gray.m, scripts/image/gray2ind.m,
scripts/image/hot.m, scripts/image/hsv.m, scripts/image/image.m,
scripts/image/imagesc.m, scripts/image/imfinfo.m, scripts/image/imformats.m,
scripts/image/imread.m, scripts/image/imshow.m, scripts/image/imwrite.m,
scripts/image/iscolormap.m, scripts/image/jet.m, scripts/image/lines.m,
scripts/image/ntsc2rgb.m, scripts/image/ocean.m, scripts/image/pink.m,
scripts/image/prism.m, scripts/image/rainbow.m, scripts/image/rgb2ntsc.m,
scripts/image/spinmap.m, scripts/image/spring.m, scripts/image/summer.m,
scripts/image/white.m, scripts/image/winter.m:
Update docstrings to have one sentence summary as first line.
Re-structure to have line lengths <= 80 chars.
author | Rik <rik@octave.org> |
---|---|
date | Sun, 03 May 2015 09:36:20 -0700 |
parents | 9fc020886ae9 |
children |
line wrap: on
line source
## Copyright (C) 2009-2015 Kai Habel ## ## 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{div} =} divergence (@var{x}, @var{y}, @var{z}, @var{fx}, @var{fy}, @var{fz}) ## @deftypefnx {Function File} {@var{div} =} divergence (@var{fx}, @var{fy}, @var{fz}) ## @deftypefnx {Function File} {@var{div} =} divergence (@var{x}, @var{y}, @var{fx}, @var{fy}) ## @deftypefnx {Function File} {@var{div} =} divergence (@var{fx}, @var{fy}) ## Calculate divergence of a vector field given by the arrays @var{fx}, ## @var{fy}, and @var{fz} or @var{fx}, @var{fy} respectively. ## ## @tex ## $$ ## div F(x,y,z) = \partial_x{F} + \partial_y{F} + \partial_z{F} ## $$ ## @end tex ## @ifnottex ## ## @example ## @group ## d d d ## div F(x,y,z) = -- F(x,y,z) + -- F(x,y,z) + -- F(x,y,z) ## dx dy dz ## @end group ## @end example ## ## @end ifnottex ## The coordinates of the vector field can be given by the arguments @var{x}, ## @var{y}, @var{z} or @var{x}, @var{y} respectively. ## ## @seealso{curl, gradient, del2, dot} ## @end deftypefn ## Author: Kai Habel <kai.habel@gmx.de> function retval = divergence (varargin) fidx = 1; if (nargin == 2) sz = size (varargin{fidx}); dx = (1:sz(2))(:); dy = (1:sz(1))(:); elseif (nargin == 3) sz = size (varargin{fidx}); dx = 1:sz(2); dy = 1:sz(1); dz = 1:sz(3); elseif (nargin == 4) fidx = 3; dx = varargin{1}(1,:); dy = varargin{2}(:,1); elseif (nargin == 6) fidx = 4; dx = varargin{1}(1,:,1)(:); dy = varargin{2}(:,1,1)(:); dz = varargin{3}(1,1,:)(:); else print_usage (); endif if (nargin == 4 || nargin == 2) if (! size_equal (varargin{fidx},varargin{fidx + 1})) error ("divergence: size of X and Y must match"); elseif (ndims (varargin{fidx}) != 2) error ("divergence: expected two-dimensional matrices X and Y"); elseif (length (dx) != columns (varargin{fidx}) || length (dy) != rows (varargin{fidx})) error ("divergence: size of dx and dy must match the respective dimension of X and Y"); endif retval = gradient (varargin{fidx}, dx, dy); retval += gradient (varargin{fidx + 1}.', dy, dx).'; elseif (nargin == 6 || nargin == 3) if (! size_equal (varargin{fidx},varargin{fidx + 1},varargin{fidx + 2})) error ("divergence: size of X, Y, and Z must match"); elseif (ndims (varargin{fidx}) != 3) error ("divergence: expected two-dimensional matrices X, Y, and Z"); elseif ((length (dx) != size (varargin{fidx}, 2)) || (length (dy) != size (varargin{fidx}, 1)) || (length (dz) != size (varargin{fidx}, 3))) error ("divergence: size of dx, dy, and dz must match the respective dimesion of X, Y, and Z"); endif ## x-direction retval = gradient (varargin{fidx}, dx, dy, dz); ## y-direction retval += shiftdim (gradient (shiftdim (varargin{fidx + 1}, 2), dy), 1); ## z-direction retval += shiftdim (gradient (shiftdim (varargin{fidx + 2}, 1), dz), 2); endif endfunction %!test %! [X,Y] = meshgrid (-20:20,-22:22); %! div = divergence (X-Y,Y); %! assert (all (div(:) == 2)); %! assert (size_equal (X,Y,div));