update packages

[CreaPhase.git] / octave_packages / m / general / bitcmp.m

diff --git a/octave_packages/m/general/bitcmp.m b/octave_packages/m/general/bitcmp.m
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+## Copyright (C) 2004-2012 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 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} {} bitcmp (@var{A}, @var{k})
+## Return the @var{k}-bit complement of integers in @var{A}.  If
+## @var{k} is omitted @code{k = log2 (bitmax) + 1} is assumed.
+##
+## @example
+## @group
+## bitcmp (7,4)
+##   @result{} 8
+## dec2bin (11)
+##   @result{} 1011
+## dec2bin (bitcmp (11, 6))
+##   @result{} 110100
+## @end group
+## @end example
+## @seealso{bitand, bitor, bitxor, bitset, bitget, bitcmp, bitshift, bitmax}
+## @end deftypefn
+
+## Liberally based on the version by Kai Habel from octave-forge
+
+function C = bitcmp (A, k)
+
+  if (nargin < 1 || nargin > 2)
+    print_usage ();
+  endif
+
+  if (nargin == 2 && (! isscalar (k) || (floor (k) != k)))
+    error ("bitcmp: K must be a scalar integer");
+  endif
+
+  if (isa (A, "double"))
+    bmax = bitmax;
+    amax = ceil (log2 (bmax));
+  else
+    if (isa (A, "uint8"))
+      amax = 8;
+    elseif (isa (A, "uint16"))
+      amax = 16;
+    elseif (isa (A, "uint32"))
+      amax = 32;
+    elseif (isa (A, "uint64"))
+      amax = 64;
+    elseif (isa (A, "int8"))
+      amax = 8;
+    elseif (isa (A, "int16"))
+      amax = 16;
+    elseif (isa (A, "int32"))
+      amax = 32;
+    elseif (isa (A, "int64"))
+      amax = 64;
+    else
+      error ("bitcmp: invalid class %s", class (A));
+    endif
+    bmax = intmax (class (A));
+  endif
+
+  if (nargin == 1 || k == amax)
+    C = bitxor (A, bmax);
+  else
+    m = double (k);
+    if (any (m < 1) || any (m > amax))
+      error ("bitcmp: K must be in the range [1,%d]", amax);
+    endif
+    mask = bitshift (bmax, k - amax);
+    C = bitxor (bitand (A, mask), mask);
+  endif
+endfunction
+
+
+%!test
+%! Amax=53;
+%! Bmax = bitmax;
+%! A = bitshift(Bmax,-2);
+%! assert(bitcmp(A,Amax),bitor(bitshift(1,Amax-1),bitshift(1,Amax-2)));
+%! assert(bitcmp(A,Amax-1),bitshift(1,Amax-2));
+%! assert(bitcmp(A,Amax-2),0);
+%!test
+%! Amax=8;
+%! Bmax = intmax('uint8');
+%! A = bitshift(Bmax,-2);
+%! assert(bitcmp(A,Amax),bitor(bitshift(uint8(1),Amax-1),bitshift(uint8(1),Amax-2)));
+%! assert(bitcmp(A,Amax-1),bitshift(uint8(1),Amax-2));
+%! assert(bitcmp(A,Amax-2),uint8(0));
+%!test
+%! Amax=16;
+%! Bmax = intmax('uint16');
+%! A = bitshift(Bmax,-2);
+%! assert(bitcmp(A,Amax),bitor(bitshift(uint16(1),Amax-1),bitshift(uint16(1),Amax-2)));
+%! assert(bitcmp(A,Amax-1),bitshift(uint16(1),Amax-2));
+%! assert(bitcmp(A,Amax-2),uint16(0));
+%!test
+%! Amax=32;
+%! Bmax = intmax('uint32');
+%! A = bitshift(Bmax,-2);
+%! assert(bitcmp(A,Amax),bitor(bitshift(uint32(1),Amax-1),bitshift(uint32(1),Amax-2)));
+%! assert(bitcmp(A,Amax-1),bitshift(uint32(1),Amax-2));
+%! assert(bitcmp(A,Amax-2),uint32(0));
+%!test
+%! Amax=64;
+%! Bmax = intmax('uint64');
+%! A = bitshift(Bmax,-2);
+%! assert(bitcmp(A,Amax),bitor(bitshift(uint64(1),Amax-1),bitshift(uint64(1),Amax-2)));
+%! assert(bitcmp(A,Amax-1),bitshift(uint64(1),Amax-2));
+%! assert(bitcmp(A,Amax-2),uint64(0));
+