Mercurial > hg > octave-nkf
view scripts/general/bitget.m @ 5915:b2e1be30c8e9 ss-2-9-7
[project @ 2006-07-28 18:08:56 by jwe]
author | jwe |
---|---|
date | Fri, 28 Jul 2006 18:08:56 +0000 |
parents | 2618a0750ae6 |
children | 34f96dd5441b |
line wrap: on
line source
## Copyright (C) 2004 David BAteman ## ## This program 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 of the License, or ## (at your option) any later version. ## ## This program 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 this program; if not, write to the Free Software ## Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA ## 02110-1301 USA ## -*- texinfo -*- ## @deftypefn {Function File} {@var{X} =} bitget (@var{a},@var{n}) ## Return the status of bit(s) @var{n} of unsigned integers in @var{a} ## the lowest significant bit is @var{n} = 1. ## ## @example ## bitget (100, 8:-1:1) ## @result{} 0 1 1 0 0 1 0 0 ## @end example ## @seealso{bitand, bitor, bitxor, bitset, bitcmp, bitshift, bitmax} ## @end deftypefn ## Liberally based of the version by Kai Habel from octave-forge function X = bitget (A, n) if (nargin != 2) usage ("bitget (A, n)"); endif if (isa (A, "double")) Amax = log2 (bitmax) + 1; _conv = @double; else if (isa (A, "uint8")) Amax = 8; _conv = @uint8; elseif (isa (A, "uint16")) Amax = 16; _conv = @uint16; elseif (isa (A, "uint32")) Amax = 32; _conv = @uint32; elseif (isa (A, "uint64")) Amax = 64; _conv = @uint64; elseif (isa (A, "int8")) Amax = 8; _conv = @int8; elseif (isa (A, "int16")) Amax = 16; _conv = @int16; elseif (isa (A, "int32")) Amax = 32; _conv = @int32; elseif (isa (A, "int64")) Amax = 64; _conv = @int64; else error ("invalid class %s", class (A)); endif endif m = double (n(:)); if (any (m < 1) || any (m > Amax)) error ("n must be in the range [1,%d]", Amax); endif X = bitand (A, bitshift (_conv (1), uint8 (n) - uint8 (1))) != _conv (0); endfunction