How can I close an old figure when a new figure is plotted?

In my code I have a slider that is moved by the user. Each time it moves, it updates a value used for a calculation, which is plotted in a new figure. Thereby, each time the slider is moved, a new figure opens. I end up having a large number of figures, so I would like to close the old figure when the new one is created.

Any help is appreciated.

Answer 1

[Steven Lord]

Why not just have the slider callback update the graphics in a figure opened for that purpose when your GUI was initialized? Why create a whole new figure?

[KirbyG_]

I have one plot in my GUI, and a subplot (2 by 1) in the figure window. I would put the subplot in the GUI as well but I dont know how to do this while ensuring my code works.

[Walter Roberson]

We don't know either, as we have not seen your code.

Answer 2

[Image Analyst]

In the slider callback I think you can just have

global hFigure; % Get handle to existing figure.
try
    close(hFigure); % Close it
catch
    % Get here if figure doesn't exist, but just ignore the error.
end
hFigure = figure;
plot(.................

Or maybe you can use exist instead of try/catch

if exist('hFigure', 'var')  % See if global variable exists yet.
    close(hFigure); % Close it
end
global hFigure; % Instantiate new global variable.
hFigure = figure;
plot(.................

There are other ways (more complicated I think) so let us know if neither of those works.