--- /dev/null
+## Copyright (C) 2002 Etienne Grossmann <etienne@egdn.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; if not, see <http://www.gnu.org/licenses/>.
+
+## opt = optimset_compat (...) - manipulate m*tlab-style options structure
+##
+## This function returns a m*tlab-style options structure that can be used
+## with the fminunc() function. 'optimset_compat' has been deprecated in
+## favor of 'optimset', which is now part of core Octave. This function
+## will possibly be removed from future versions of the 'optim' package.
+##
+## INPUT : Input consist in one or more structs followed by option-value
+## pairs. The option that can be passed are those of m*tlab's 'optimset'.
+## Whether fminunc() accepts them is another question (see fminunc()).
+##
+## Two extra options are supported which indicate how to use directly octave
+## optimization tools (such as minimize() and other backends):
+##
+## "MinEquiv", [on|off] : Tell 'fminunc()' not to minimize 'fun', but
+## instead return the option passed to minimize().
+##
+## "Backend", [on|off] : Tell 'fminunc()' not to minimize 'fun', but
+## instead return the [backend, opt], the name of the
+## backend optimization function that is used and the
+## optional arguments that will be passed to it. See
+## the 'backend' option of minimize().
+
+function opt = optimset_compat (varargin)
+
+## Diagnostics , ["on"|{"off"}] :
+## DiffMaxChange, [scalar>0] : N/A (I don't know what it does)
+## DiffMinChange, [scalar>0] : N/A (I don't know what it does)
+## Display , ["off","iter","notify","final"]
+## : N/A
+
+ persistent warned = false;
+ if (! warned)
+ warned = true;
+ warning ("Octave:deprecated-function",
+ "`optimset_compat' has been deprecated, and will be removed in the future. Use `optimset' from Octave core instead.");
+ endif
+
+args = varargin;
+
+opt = struct ();
+
+ # Integrate all leading structs
+
+while length (args) && isstruct (o = args{1})
+
+ args = args(2:length(args)); # Remove 1st element of args
+ # Add key/value pairs
+ for [v,k] = o, opt = setfield (opt,k,v); end
+end
+
+## All the option
+op1 = [" DerivativeCheck Diagnostics DiffMaxChange DiffMinChange",\
+ " Display GoalsExactAchieve GradConstr GradObj Hessian HessMult",\
+ " HessPattern HessUpdate Jacobian JacobMult JacobPattern",\
+ " LargeScale LevenbergMarquardt LineSearchType MaxFunEvals MaxIter",\
+ " MaxPCGIter MeritFunction MinAbsMax PrecondBandWidth TolCon",\
+ " TolFun TolPCG TolX TypicalX ",\
+ " MinEquiv Backend "];
+
+opt = read_options (args, "op1",op1, "default",opt,"prefix",1,"nocase",1);