Is it possible to manipulate a single field within a 'UserData' structure of a figure or axis ???

We have used the 'UserData' property of a MATLAB figure's axes to store various data. That's why we have chosen to define 'UserData' as a structure.

Because we have stored a considerable amount of data within the structure, we would like to avoid manipulating single fields with get/set commands which can only access the 'UserData' property as a whole (as far as I know). Manipulating as a whole is time consuming.

Does anybody know a way to manipulate the single fields of the structure directly?

Many Thanks

Ulrich

[Matt Raum]

Ulrich,

I'd love to know if you found any answers to this because I have exactly the same problem.

I develop GUI's which sometimes need to store a large amount of data internally and I do this by making the 'userdata' property a structure. The problem is that in order to pull one small field I am forced to first assign the 'userdata' property value to another variable from which I can access a single field. If the 'userdata' structure also contains large data fields then the assignment (and therefore the time to access even a small data field) is very time consuming.

Answer 1

[Walter Roberson]

No. But see getappdata() / setappdata(), which in essence allow you to work at the struct field level.

You should also be considering storing the handles to objects instead of the objects themselves, as pulling back a struct filled with handles and accessing one of the handles is going to be much faster than pulling back a struct filled with the content of everything.

[Matt Raum]

Thanks for the good advice Walter, these fit the bill perfectly. My new implementation using these functions is much snappier than my old one.

[Kulbhushan Chand]

I am not able to figure out how to use the setappdata() to modify only a particular field in a structure (as asked in the question). What should be the correct syntax?