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## Copyright (C) 1996-2024 The Octave Project Developers
##
## See the file COPYRIGHT.md in the top-level directory of this
## distribution or <https://octave.org/copyright/>.
##
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## -*- texinfo -*-
## @deftypefn {} {@var{n} =} rindex (@var{s}, @var{t})
## Return the position of the last occurrence of the character string
## @var{t} in the character string @var{s}, or 0 if no occurrence is
## found.
##
## @var{s} may also be a string array or cell array of strings.
##
## For example:
##
## @example
## @group
## rindex ("Teststring", "t")
##      @result{} 6
## @end group
## @end example
##
## The @code{rindex} function is equivalent to @code{index} with
## @var{direction} set to @qcode{"last"}.
##
## @seealso{find, index}
## @end deftypefn

function n = rindex (s, t)

  if (nargin != 2)
    print_usage ();
  endif

  n = index (s, t, "last");

endfunction


%!assert (rindex ("foobarbaz", "b"), 7)
%!assert (rindex ("foobarbaz", "o"), 3)

%!test
%! str = char ("Hello", "World", "Goodbye", "World");
%! assert (rindex (str, "o"), [5; 2; 3; 2]);
%! str = cellstr (str);
%! assert (rindex (str, "o"), [5; 2; 3; 2]);

## Test input validation
%!error <Invalid call> rindex ()
%!error rindex ("foo")
%!error rindex ("foo", "bar", "last")