How determine type of plot object?

Say, I am given an axes containing unknown plot objects. I am searching for a way to determine the type of these plot objects, i.e. I would like to know whether they are a lineseries object, a barseries object, an errorbarseries object, etc.

For core graphics objects (e.g. line, patch, surface, text,...) this isn't a problem because one can query the object's 'type' property,

get(h, 'Type').

However, most plot objects such as barseries or areaseries return 'hggroup' as type.

I have tried to find unique properties of each plot object type (e.g. 'BarPeers' for barseries objects) and then used a cascade of isprop calls to identify the plot object, but this obviously isn't very elegant.

Matlab itself seems to know the plot object type, because e.g.

set(handle_of_barseries_object, 'Color','r')

returns the error message "The name 'Color' is not an accessible property for an instance of class 'barseries'." So the plot object type must be determinable somehow.

Any ideas?

Stephan.

Answer 1

[Julian Hapke]

here's the probably dirtiest code I've written so far, but does, what you want:

% make an example plot with several classes
figure;
hold on;
X=rand(10,1);Y=rand(10,1);X=sort(X);Y=sort(Y);
plot(X,Y);
errorbar(X,Y);
bar(X,Y);
barh(X,Y);
contour([X Y],[Y X]);
    
plts = get(gca,'Children');

% determine plot class by catching the error message that is
% generated when a nonexistent property is addressed

type = cell(size(plts));

for kk = 1:length(plts)
    try
        get(plts(kk),'nonexistent')
    catch err
        tmp = strfind(err.message,'''');
        type{kk} = err.message(tmp(end-1)+1:tmp(end)-1);
    end
end

regards

julian

[Stephan Heise]

That's a good idea! Thanks Julian.

[Julian Hapke]

Addon:

From 2014b on you can use the

class(h)

function to get information about your plot handle and its class.

[Julian Hapke]

just found out that pre 2014b

class(handle(h))

also does the trick