## Copyright (C) 2000 Paul Kienzle <pkienzle@users.sf.net>
##
## 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; see the file COPYING. If not, see
## <https://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn {Function File} {} boxcar (@var{m})
## Return the filter coefficients of a rectangular window of length @var{m}.
## @end deftypefn

function w = boxcar (m)

  if (nargin != 1)
    print_usage ();
  elseif (! (isscalar (m) && (m == fix (m)) && (m > 0)))
    error ("boxcar: M must be a positive integer");
  endif

  w = ones(m, 1);

endfunction

%!assert (boxcar (1), 1)
%!assert (boxcar (2), ones (2, 1))
%!assert (boxcar (100), ones (100, 1))

%% Test input validation
%!error boxcar ()
%!error boxcar (0.5)
%!error boxcar (-1)
%!error boxcar (ones (1, 4))
%!error boxcar (1, 2)
