Mercurial > hg > octave-nkf
diff scripts/miscellaneous/swapbytes.m @ 6869:f9c893831e68
[project @ 2007-09-06 16:38:44 by dbateman]
author | dbateman |
---|---|
date | Thu, 06 Sep 2007 16:38:44 +0000 |
parents | |
children | 93c65f2a5668 |
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new file mode 100644 --- /dev/null +++ b/scripts/miscellaneous/swapbytes.m @@ -0,0 +1,57 @@ +## Copyright (C) 2007 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, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +## 02110-1301, USA. + +## -*- texinfo -*- +## @deftypefn {Function File} {} swapbytes (@var{x}) +## Swaps the byte order on values, converting from little endian to big +## endian and visa-versa. For example +## +## @example +## @group +## swapbytes (uint16 (1:4)) +## @result{} [ 256 512 768 1024] +## @end group +## @end example +## +## @seealso{typecast, cast} +## @end deftypefn + +function y = swapbytes (x) + if (nargin != 1) + print_usage (); + endif + + clx = class (x); + if (strcmp (clx, "int8") || strcmp (clx, "uint8") || isempty (x)) + y = x; + else + if (strcmp (clx, "int16") || strcmp (clx, "uint16")) + nb = 2; + elseif (strcmp (clx, "int32") || strcmp (clx, "uint32")) + nb = 4; + elseif (strcmp (clx, "int64") || strcmp (clx, "uint64") || + strcmp (clx, "double")) + nb = 8; + else + error ("swapbytes: invalid class of object"); + endif + y = reshape (typecast (reshape (typecast (x(:), "uint8"), nb, numel (x)) + ([nb : -1 : 1], :) (:), clx), size(x)); + endif +endfunction