Mercurial > hg > octave-nkf
changeset 5012:ed25bed43409
[project @ 2004-09-21 15:45:48 by jwe]
author | jwe |
---|---|
date | Tue, 21 Sep 2004 15:45:48 +0000 |
parents | 1743bf921773 |
children | 1eb9ce5c0152 |
files | scripts/general/flipdim.m scripts/general/rotdim.m |
diffstat | 2 files changed, 188 insertions(+), 0 deletions(-) [+] |
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new file mode 100644 --- /dev/null +++ b/scripts/general/flipdim.m @@ -0,0 +1,67 @@ +## Copyright (C) 2004 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 2, 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, write to the Free +## Software Foundation, 59 Temple Place - Suite 330, Boston, MA +## 02111-1307, USA. + +## -*- texinfo -*- +## @deftypefn {Function File} {} flipdim (@var{x}, @var{dim}) +## Return a copy of @var{x} flipped about the dimension @var{dim}. +## For exmaple +## +## @example +## @group +## flipdim ([1, 2; 3, 4], 2) +## @result{} 2 1 +## 4 3 +## @end group +## @end example +## @end deftypefn +## @seealso{fliplr, flipud, rot90 and rotdim} + +## Author: David Bateman + +function y = flipdim (x, dim) + + if (nargin != 1 && nargin != 2) + usage ("flipdim (x, dim)"); + endif + + nd = ndims (x); + sz = size (x); + if (nargin == 1) + ## Find the first non-singleton dimension. + dim = 1; + while (dim < nd + 1 && sz(dim) == 1) + dim = dim + 1; + endwhile + if (dim > nd) + dim = 1; + endif + else + if (! (isscalar (dim) && dim == round (dim)) && dim > 0 && dim < (nd + 1)) + error ("flipdim: dim must be an integer and valid dimension"); + endif + endif + + idx = cell (); + for i = 1:nd + idx{i} = 1:sz(i); + endfor + idx{dim} = sz(dim):-1:1; + y = x(idx{:}); + +endfunction
new file mode 100644 --- /dev/null +++ b/scripts/general/rotdim.m @@ -0,0 +1,121 @@ +## Copyright (C) 2004 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 2, 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, write to the Free +## Software Foundation, 59 Temple Place - Suite 330, Boston, MA +## 02111-1307, USA. + +## -*- texinfo -*- +## @deftypefn {Function File} {} rotdim (@var{x}, @var{n}, @var{plane}) +## Return a copy of @var{x} with the elements rotated counterclockwise in +## 90-degree increments. The second argument is optional, and specifies +## how many 90-degree rotations are to be applied (the default value is 1). +## The third argument is also optional and defines the plane of the +## rotation. As such @var{plane} is a two element vector containing two +## different valid dimensions of the matrix. If @var{plane} is not given +## Then the first two non-singleton dimensions are used. +## +## Negative values of @var{n} rotate the matrix in a clockwise direction. +## For example, +## +## @example +## @group +## rotdim ([1, 2; 3, 4], -1, [1, 2]) +## @result{} 3 1 +## 4 2 +## @end group +## @end example +## +## @noindent +## rotates the given matrix clockwise by 90 degrees. The following are all +## equivalent statements: +## +## @example +## @group +## rot90 ([1, 2; 3, 4], -1, [1, 2]) +## @equiv{} +## rot90 ([1, 2; 3, 4], 3, [1, 2]) +## @equiv{} +## rot90 ([1, 2; 3, 4], 7, [1, 2]) +## @end group +## @end example +## @end deftypefn +## @seealso{rot90, flipud, fliplr and flipdim} + +function y = rotdim (x, k, plane) + + if (nargin < 1 || nargin > 3) + usage ("rotdim (x, k, plane)"); + endif + + if (nargin > 1 && !isempty(k)) + if (imag (k) != 0 || fix (k) != k) + error ("rotdim: k must be an integer"); + endif + else + k = 1; + endif + + nd = ndims (x); + sz = size (x); + if (nargin < 3) + ## Find the first two non-singleton dimension. + plane = []; + dim = 0; + while (dim < nd) + dim = dim + 1; + if (sz (dim) != 1) + plane = [plane, dim]; + if (length (plane) == 2) + break; + endif + endif + endwhile + if (length (plane) < 1) + plane = [1, 2]; + elseif (length (plane) < 2) + plane = [1, plane]; + endif + else + if (! (isvector (plane) && length (plane) == 2 + && all (plane == round (plane)) && all (plane > 0) + && all (plane < (nd + 1)) && plane(1) != plane(2))) + error ("rotdim: plane must be a 2 element integer vector defining a valid plane"); + endif + endif + + k = rem (k, 4); + if (k < 0) + k = k + 4; + endif + if (k == 0) + y = x; + elseif (k == 2) + y = flipdim (flipdim (x, plane (1)), plane (2)); + elseif (k == 1 || k == 3) + perm = 1:nd; + perm(plane(1)) = plane(2); + perm(plane(2)) = plane(1); + y = permute (x, perm); + if (k == 1) + y = flipdim (y, min (plane)); + else + y = flipdim (y, max (plane)); + endif + else + error ("rotdim: internal error!"); + endif + +endfunction