Creating an interactive 3D bar graph

Hi, I've been struggling to create a 3D interactive bar graph.

I have the following code based off the example I found online (Here http://www.mathworks.com/help/control/ug/build-app-with-interactive-plot-updates.html)

phase = 0; % a value between 0 and 2 pi                          

amp = 0; % a value between 0 and 1                              

A(1:6,1:6) = amp; % a 6x6 matrix of with all elements set to amp

sys = CreateHologram(A,phase,4); %this is a separate method that returns an (NxM) matrix with the element at (i,j) equal to a value between 0 and 255

f = figure;

ax = axes('Parent',f,'position',[0.13 0.39  0.77 0.54]);

colormap( ColourMap() ); % a custom colourmap

h = bar3(ax,sys); % this is a 3D bar graph 

for k = 1:length(h) %The following for loop assigns bar colour based on their height

      zdata = get(h(k),'ZData');

      set(h(k),'CData',(zdata),'FaceColor','interp');

end

b = uicontrol('Parent',f,'Style','slider','Position',[81,100,419,23],'value',amp, 'min',0, 'max',1); % a 
slider

b2 = uicontrol('Parent',f,'Style','slider','Position',[81,50,419,23],'value',phase, 'min',0, 'max',2*pi); % a slider

bgcolor = [0,1,1]; 

bl8 = uicontrol('Parent',f,'Style','text','Position',[50,54,23,23],'String','0','BackgroundColor',bgcolor);

bl9 = uicontrol('Parent',f,'Style','text','Position',[500,54,23,23],'String','1','BackgroundColor',bgcolor);

bl10 = uicontrol('Parent',f,'Style','text','Position'[240,75,100,23],
'String','Phase','BackgroundColor',bgcolor);

bl11 = uicontrol('Parent',f,'Style','text','Position',[240,20,100,23],'String','Intensity','BackgroundColor',bgcolor);

bl12 = uicontrol('Parent',f,'Style','text','Position',[50,100,23,23],'String','0','BackgroundColor',bgcolor);

bl13 = uicontrol('Parent',f,'Style','text','Position',[500,100,23,23],'String','2pi','BackgroundColor',bgcolor);

set(b,'Callback',@(es,ed) updateSystem(h, CreateHologram(A,get(es,'Value'),4)  ));

So far the code executes correctly once and draws the graph with the intial values for phase and amp but as soon as I try to adjust either of the sliders the following error is generated: Undefined function 'updateSystem' for input arguments of type 'double'.

Any help is greatly appreciated

Answer 1

[Geoff Hayes]

Daniel - have you written the callback updateSystem? The error message is telling you that the function is either undefined or it cannot be found within the MATLAB search path.

You made a reference to an example that makes use of the updateSystem function which is part of the Control System Toolbox (see update dynamic system data in a response plot for details). Do you have this toolbox? In the MATLAB Window type

 ver

to list your version of MATLAB and all toolboxes that you have installed. If you don't have the toolbox (or the version that includes this function) then you will need to find an alternative.

[Daniel Rayleigh]

Hi, Thanks for the help.

I was actually able to solve the problem using a listener based approach found here: http://www.mathworks.com/matlabcentral/answers/56236-how-to-constantly-update-a-plot-off-of-a-slider-being-pulled

Thanks again