How to highlight a datapoint on comet using a slider

Hi all,

I'm very stuck with how to link a slider to a comet plot i have.

What I intend to do is, the user (once the graph has been plotted) can move the slider back and forwards which will highlight a corresponding coordinate on the graph with a label showing the data (x,y) for that point.

I would like to mention that i am a complete novice so please excuse the embarrasing code...

The current code (including all the previosuly tried code shown in comments) is:

           comet(x,y,0.1)  %this is the plot style currently
           app.Slider.Limits = [0 max(x)]
           hold(app.Graph,'on')
            
%             function app.Slider.ValueChangingFcn
%                 change = comet(app.Graph,x,y,0.1)
%                 sld = app.Slider(app.Graph,'ValueChangingFcn',@(sld,event) sliderMoving(event,change))
%             end
%             
%             function sliderMoving(event,change)
%                 [~,ind] = min(abs(x-XData))
%                 coord = sprintf('%f,%f',XData,YData)
%                 text(app.Graph,x(ind),y(ind),coord)
%             end
%         function sliderchanging
%             changingValue = event.Value;

            function sliderchanging(app, event)  
            b = app.Slider.Value
            %YData = y(XData)
            %X = num2str(XData)
            %Y = num2str(YData)
            %b = char2num(app.Slider.ValueChangedFcn)
            [minValue, closestIndex] = min(abs(x - b.')) %this shows an error for 
            XData = x(closestIndex)
            YData = y(x==XData)
            %[~,ind] = min(abs(x=XData))
            coord = sprintf('\leftarrow %.1f,%.1f',XData,YData)
            text(app.Graph,x(XData),y(XData),coord)
            plot(app.Graph,x(XData),y(XData),'ko')
         end
           %plot(app.Graph,x(x==app.Slider.Value),y(x==app.Slider.Value));
%            XData = app.Slider.Value
%            YData = y(x==XData)
%            X = num2str(XData)
%            Y = num2str(YData)
%            coord = sprintf('%f,%f',XData,YData)
%            text(app.Graph,x(x==XData),y(x==XData),coord)
           %datatip(co,x(x==app.Slider.Value),y(x==app.Slider.Value))
           
           %position = app.Slider.Value
           %ypos = y(x==position)
           %xpos = x(x==position)
           %text(app.Graph,xpos,ypos,'\leftarrow %.2f,%.2f',xpos,ypos)

[Cris LaPierre]

Don't just abandon your other question about this.