iFit/fminplot

 stop=fminplot(pars, optimValues, state) default plotting function showing the 
   criteria evolution as well as main parameters and status.
 A STOP button allows premature abortion of the optimization.
 When used after the optimization, fminplot can plot the criteria convergence 
   and parameter distributions.
 
 To use this optimization monitoring tool, use:
   options.OutputFcn='fminplot'
 prior to the optimization/fit.

 To plot the criteria convergence and parameter distributions after the 
 optimization/fit completion, use:
   [pars,fval,exitflag,output]=fmin(@objective, [], 'OutputFcn=fminplot')
   fminplot(output);

 To retrieve the optimisation history from the fminplot window, use:
   h = fminplot;

 Other defined function to be used as OutputFcn and PlotFcns:
   @fminstop           displays a stop button (very fast, allow clean abort of fit)
   @optimplotx         plots the current point
   @optimplotfval      plots the function value
   @optimplotfunccount plots the function count

 example: 
   fmin(@objective, [], 'OutputFcn=fminplot')