Creating a standalone application with dynamic data objects

I have an application that processes input using data models that are in .mat files. I've added the models to the build using the -a flag; however, I'd like to let the user specify the models to use when they run the application. Ideally something like

./my_app data/folder/1 data/folder/2

where the inputs are the paths to the .mat files that get loaded using load(). Is it possible to specify the .mat files after the application has been compiled and distrubted, or does the Matlab Compiler require that the .mat files be added prior to compilation?

Answer 1

[Walter Roberson]

The compiler does not require that the .mat files be added prior to compilation. However, if you use

load(filename)

instead of

result = load(filename)

then you may run into problems with variables that are to be loaded into the workspace. It is best to not "poof" new variables into place using load() or evalin() or assignin() or eval()

[Sean]

Thanks for the reply. The .mat files are currently loaded and assigned to variables such as result = load(filename), which works fine in matlab. But when the standalone app is run, an error is thrown for attempting to access a non-existant member of a struct when I later try to use result.somemember.

[Walter Roberson]

As a debugging step, display fieldnames() of the structure right after the load(), and also use whos('-file','TheFileName') on the .mat file to see the variables saved in the file.

[Sean]

I get the following warning

Warning: Variable 'var' originally saved as a 'Object type' cannot be instantiated as an object and will be read in as a uint32.

And then fieldnames fails, as it's called on a uint32.

After doing some research, it seems like the classdef needs to be included in the compilation either using the %#function pragma, or somehow including the classdef (not sure I have this) in the compilation. However, this is what I want to avoid--I'd like people to be able to run the app with their own models.

[Walter Roberson]

Are you trying to import objects from the .mat file where you do not care what the actual objects are as long as they have some particular set of methods that your exe applies to them? If so then I do not know if it is possible to support that.