How do I dynamically add new subplots to a figure in MATLAB 7.9 (R2009b)?

Why is there only one subplot axis seen instead of two when I execute the following code?

>> figure(1), subplot(1,1,1)

>> subplot(2,1,2)

I am expecting my current axis to remain as I increase the number of subplots that I add to my figure. My use case is that I would like to create figures dynamically in a GUI using GUIDE, such that when the user clicks a button, it will add new subplots to the current figure.

Answer 1

[MathWorks Support Team]

When you are creating new subplots, such as subplot(1,1,1), then subplot(2,1,2), the new subplot specification causes a new axis to overlap an existing axis, so the existing axis is deleted - unless the position of the new and existing axis are identical.

However, if you would like to dynamically create subplots, you can first get a handle to the current axes, then change the position of the axes when new you would like to create new axes. Start with a plot with one axis:

figure1 = figure; %get a handle to a new figure
plot(1:10)
axes1 = gca; %get a handle to this axis

Now, to create a new subplot below this one, change the axes position for the current axes:

% move the axes1 position
set(axes1,'OuterPosition',[0 0.5 1 0.5]);

% Create 2nd axes and set the position below the first axis
axes2 = axes('Parent',figure1,'OuterPosition',[0 0 1 0.5]);
plot(axes2,1:20,1:20)

Where 'OuterPosition' is specified as[left bottom width height]

It may also be useful to use the command PLOTTOOLS, which will allow you to create plots, and then generate m code to view those plots (in plottools gui, File > Generate code). This will allow you to create and view examples with the axes 'position' property.