## 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
## @end deftypefn
##
## @seealso{bitand, bitor, bitxor, bitset, bitcmp, bitshift, bitmax}

## 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