## Copyright (C) 1996-2011 Kurt Hornik
##
## 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} {@var{x} =} str2num (@var{s})
## @deftypefnx {Function File} {[@var{x}, @var{state}] =} str2num (@var{s})
## Convert the string (or character array) @var{s} to a number (or an
## array).  Examples:
##
## @example
## @group
## str2num("3.141596")
##      @result{} 3.141596
##
## str2num(["1, 2, 3"; "4, 5, 6"]);
##      @result{} ans =
##         1  2  3
##         4  5  6
## @end group
## @end example
##
## The optional second output, @var{state}, is logically true when the
## coversion is successful. If the conversion fails the numeric output,
## @var{n}, is empty and @var{state} is false.
##
## @strong{Caution:} As @code{str2num} uses the @code{eval} function
## to do the conversion, @code{str2num} will execute any code contained
## in the string @var{s}.  Use @code{str2double} instead if you want to
## avoid the use of @code{eval}.
## @seealso{str2double, eval}
## @end deftypefn

## Author: jwe

function [m, state] = str2num (s)

  if (nargin == 1 && ischar (s))
    [nr, nc] = size (s);
    sep = ";";
    sep = sep (ones (nr, 1), 1);
    s = sprintf ("m = [%s];", reshape ([s, sep]', 1, nr * (nc + 1)));
    state = true;
    eval (s, "m = []; state = false;");
    if (ischar (m))
      m = [];
      state = false;
    endif
  else
    print_usage ();
  endif

endfunction

%!assert(str2num ("-1.3e2") == -130 && str2num ("[1, 2; 3, 4]") == [1, 2; 3, 4]);

%!error str2num ();

%!error str2num ("string", 1);

%!test
%! [x, state] = str2num ("pi");
%! assert (state)
%! [x, state] = str2num (tmpnam);
%! assert (! state)
