optimget.m

% Copyright (C) 2008 Jaroslav Hajek
% Copyright (C) 2009 VZLU Prague
%
% 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} {} optimget (@var{options}, @var{parname})
% @deftypefnx {Function File} {} optimget (@var{options}, @var{parname}, @var{default})
% Return a specific option from a structure created by
% @code{optimset}.  If @var{parname} is not a field of the @var{options}
% structure, return @var{default} if supplied, otherwise return an
% empty matrix.
% @end deftypefn

function retval = optimget (options, parname, default)

  if (nargin < 2 || nargin > 4 || ~ isstruct (options) || ~ ischar (parname))
    print_usage ();
  end

  % opts = all_opts__ ();
  opts = { 'ComplexEqn', 'FinDiffType', 'FunValCheck', 'GradObj', 'Jacobian', 'MaxFunEvals', 'MaxIter', 'OutputFcn', 'TolFun', 'TolX', 'Updating' };
  idx = lookup (opts, parname, 'i');

  if (idx > 0 && strcmpi (parname, opts{idx}))
    parname = opts{idx};
  else
    warning ('unrecognized option: %s', parname);
  end
  if (isfield (options, parname))
    retval = options.(parname);
  elseif (nargin > 2)
    retval = default;
  else
    retval = [];
  end

end

function idx = lookup( opts, parname, caseq )
    if ( strcmp('caseq','i')  )
        for i = 1:length(opts)
            if ( strcmpi(opts{i},parname)  )
                idx = i;
                return;
            end
        end
    else
        for i = 1:length(opts)
            if ( strcmp(opts{i},parname)  )
                idx = i;
                return;
            end
        end
    end
    idx = -1;
    return;
end