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## -*- texinfo -*-
## @deftypefn {} {} fliplr (@var{x})
## Flip array left to right.
##
## Return a copy of @var{x} with the order of the columns reversed.  In other
## words, @var{x} is flipped left-to-right about a vertical axis.  For example:
##
## @example
## @group
## fliplr ([1, 2; 3, 4])
##      @result{}  2  1
##          4  3
## @end group
## @end example
##
## @seealso{flipud, flip, rot90, rotdim}
## @end deftypefn

function y = fliplr (x)

  if (nargin < 1)
    print_usage ();
  endif

  y = flip (x, 2);

endfunction


%!assert (fliplr ([1, 2; 3, 4]), [2, 1; 4, 3])
%!assert (fliplr ([1, 2; 3, 4; 5, 6]), [2, 1; 4, 3; 6, 5])
%!assert (fliplr ([1, 2, 3; 4, 5, 6]), [3, 2, 1; 6, 5, 4])
%!assert (fliplr ([1 2 3].'), [1 2 3].')

## Test NDArrays
%!test
%! a(:,:,1) = [ 1  2;  3  4;  5  6];
%! a(:,:,2) = [ 7  8;  9 10; 11 12];
%! b(:,:,1) = [ 2  1;  4  3;  6  5];
%! b(:,:,2) = [ 8  7; 10  9; 12 11];
%! assert (fliplr (a), b);

## Test NDArray with singleton dimensions
%!test
%! a(:,:,:,1) = [ 1  2;  3  4;  5  6];
%! a(:,:,:,2) = [ 7  8;  9 10; 11 12];
%! b(:,:,:,1) = [ 2  1;  4  3;  6  5];
%! b(:,:,:,2) = [ 8  7; 10  9; 12 11];
%! assert (fliplr (a), b);

## Test for 1 row, i.e., returns the same
%!test
%! a(:,1,:,1) = [ 1  2  3  4];
%! a(:,1,:,2) = [ 5  6  7  8];
%! assert (fliplr (a), a);

## Test input validation
%!error <Invalid call> fliplr ()
