Optimization plot in App Designer

My App Designer program runs an optimization process. Specifically with the fmincon algorithm.

I would like to plot the real-time optimization process so that the user can watch it evolve. Specifically I want to plot 'optimplotx' and 'optimplotfval'.

However, I would like to plot these two graphs within two UIAxes elements in my App, and not in a pop-up window as it does by default.

My question is if it is possible to easily transfer those two plots that the optimization algorithm create (and updates) by default to their respective UIAxes elements.

By easily I mean not having to code all the plotting process (input data, plotting, updating...) but rather "associating" the actual graphs that pop-up to the UIAxes in the App.

Thanks in advance.

Answer 1

[Kevin Holly]

You could get the handle of the axes and transfer the children to the uiaxes in your app. See example code below:

fun = @(x)100*(x(2)-x(1)^2)^2 + (1-x(1))^2;
nonlcon = @unitdisk;
A = [];
b = [];
Aeq = [];
beq = [];
lb = [];
ub = [];
x0 = [0,0];

options = optimoptions('fmincon','PlotFcn',@optimplotx);
[x,fval,exitflag,output,lambda,grad,hessian] = fmincon(fun,x0,A,b,Aeq,beq,lb,ub,nonlcon,options);

h = gca;
h.Children.Parent = app.UIAxes;
app.UIAxes.XLabel.String = h.XLabel.String;
app.UIAxes.YLabel.String = h.YLabel.String;
app.UIAxes.Title.String = h.Title.String;
app.UIAxes.XLim = h.XLim;
app.UIAxes.YLim = h.YLim;
close(gcf)

[Kevin Holly]

Here is an example if you are transferring two plots:

fun = @(x)100*(x(2)-x(1)^2)^2 + (1-x(1))^2;
nonlcon = @unitdisk;
A = [];
b = [];
Aeq = [];
beq = [];
lb = [];
ub = [];
x0 = [0,0];

options = optimoptions('fmincon','PlotFcn',{@optimplotx,@optimplotfval});
[x,fval,exitflag,output,lambda,grad,hessian] = fmincon(fun,x0,A,b,Aeq,beq,lb,ub,nonlcon,options);

h=gcf;
app.UIAxes.XLim = h.Children(end).XLim;
app.UIAxes.YLim = h.Children(end).YLim;
h.Children(end).Children.Parent = app.UIAxes;
app.UIAxes.XLabel.String = h.Children(end).XLabel.String;
app.UIAxes.YLabel.String = h.Children(end).YLabel.String;
app.UIAxes.Title.String = h.Children(end).Title.String;


app.UIAxes2.XLim = h.Children(end-1).XLim;
app.UIAxes2.YLim = h.Children(end-1).YLim;
h.Children(end-1).Children.Parent = app.UIAxes2;
app.UIAxes2.XLabel.String = h.Children(end-1).XLabel.String;
app.UIAxes2.YLabel.String = h.Children(end-1).YLabel.String;
app.UIAxes2.Title.String = h.Children(end-1).Title.String;
           

[Jonatan Solanas]

Thanks for your feedback.

I have tried your code, but since it is added right after the fmincon function it only executes when the optimization process ends, plotting only the end result.

As I said, I would like to plot the real-time process.

I have tried adding your code to an OutputFcn, so that it executes with every iteration.

%fmincon input...

options = optimoptions(@fmincon, 'PlotFcn',{@optimplotx,@optimplotfval},'OutputFcn',@outfun);

%fmincon...
    
function stop = outfun(x,optimValues,state)
            stop = false;

            switch state
                 case 'init'
                     hold (app.UIAxes, "on")
                     hold (app.UIAxes2, "on")
                 case 'iter'
                    h=gcf;
                    app.UIAxes.XLim = h.Children(end).XLim;
                    app.UIAxes.YLim = h.Children(end).YLim;
                    h.Children(end).Children.Parent = app.UIAxes;
                    app.UIAxes.XLabel.String = h.Children(end).XLabel.String;
                    app.UIAxes.YLabel.String = h.Children(end).YLabel.String;
                    app.UIAxes.Title.String = h.Children(end).Title.String;
        
                    app.UIAxes2.XLim = h.Children(end-1).XLim;
                    app.UIAxes2.YLim = h.Children(end-1).YLim;
                    h.Children(end-1).Children.Parent = app.UIAxes2;
                    app.UIAxes2.XLabel.String = h.Children(end-1).XLabel.String;
                    app.UIAxes2.YLabel.String = h.Children(end-1).YLabel.String;
                    app.UIAxes2.Title.String = h.Children(end-1).Title.String;
                 case 'done'
                     hold (app.UIAxes, "off")
                     hold (app.UIAxes2, "off")
                 otherwise
            end
        end

However I can't get it to work since I am getting the following error:

Error using outfun

Unrecognized field name "searchdirection".

Error in callAllOptimOutputFcns (line 13)

stop(i) = feval(OutputFcn{i},xOutputfcn,optimValues,state,varargin{:});

Error in barrier

Error in barrier

Error in barrier

Error in fmincon (line 873)

[X,FVAL,EXITFLAG,OUTPUT,LAMBDA,GRAD,HESSIAN] = barrier(funfcn,X,A,B,Aeq,Beq,l,u,confcn,options.HessFcn, ...