## Copyright (C) 2001 Laurent Mazet ## ## 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 3 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, see . ## -*- texinfo -*- ## @deftypefn {Function File} {@var{b} =} de2bi (@var{d}) ## @deftypefnx {Function File} {@var{b} =} de2bi (@var{d}, @var{n}) ## @deftypefnx {Function File} {@var{b} =} de2bi (@var{d}, @var{n}, @var{p}) ## @deftypefnx {Function File} {@var{b} =} de2bi (@var{d}, @var{n}, @var{p}, @var{f}) ## ## Convert a non-negative integer to bit vector. ## ## The variable @var{d} must be a vector of non-negative integers. @code{de2bi} ## then returns a matrix where each row represents the binary representation ## of elements of @var{d}. If @var{n} is defined then the returned matrix ## will have @var{n} columns. This number of columns can be either larger ## than the minimum needed and zeros will be added to the msb of the ## binary representation or smaller than the minimum in which case the ## least-significant part of the element is returned. ## ## If @var{p} is defined then it is used as the base for the decomposition ## of the returned values. That is the elements of the returned value are ## between '0' and 'p-1'. ## ## The variable @var{f} defines whether the first or last element of @var{b} ## is considered to be the most-significant. Valid values of @var{f} are ## "right-msb" or "left-msb". By default @var{f} is "right-msb". ## ## @seealso{bi2de} ## @end deftypefn function b = de2bi (d, n, p, f) if (nargin == 1) p = 2; n = floor ( log (max (max (d), 1)) ./ log (p) ) + 1; f = "right-msb"; elseif (nargin == 2) p = 2; f = "right-msb"; elseif (nargin == 3) if (ischar (p)) f = p; p = 2; else f = "right-msb"; endif elseif (nargin == 4) if (ischar (p)) tmp = f; f = p; p = tmp; endif else print_usage (); endif d = d(:); if (! (all (d == fix (d)) && all (d >= 0))) error ("de2bi: all elements of D must be non-negative integers"); endif if (isempty (n)) n = floor ( log (max (max (d), 1)) ./ log (p) ) + 1; endif power = ones (length (d), 1) * (p .^ [0 : n-1] ); d = d * ones (1, n); b = floor (rem (d, p*power) ./ power); if (strcmp (f, "left-msb")) b = b(:,columns (b):-1:1); elseif (!strcmp (f, "right-msb")) error ("de2bi: invalid option '%s'", f); endif endfunction %!shared x %! x = randi ([0 2^16-1], 100, 1); %!assert (de2bi (0), 0) %!assert (de2bi (1), 1) %!assert (de2bi (255), ones (1, 8)) %!assert (de2bi (255, [], 256), 255) %!assert (de2bi (1023, 8, 8), [7 7 7 1 0 0 0 0]) %!assert (size (de2bi (x, 16)), [100 16]) %!assert (de2bi (x, 16, "right-msb"), de2bi (x, 16)) %!assert (de2bi (x, 16, "left-msb"), fliplr (de2bi (x, 16))) %% Test input validation %!error de2bi () %!error de2bi (1, 2, 3, 4, 5) %!error de2bi (1, 2, 3, 4) %!error de2bi (1, 2, 3, "invalid") %!error de2bi (0.1) %!error de2bi (-1)