MEX-equivalent of INPUTNAME

All,

Is there a way, within a mexFunction, of retrieving the actual name of (the caller's) argument passed as one of the prhs parameters? Or, in other words, is there a way in MEX to do the equivalent of the inputname function as in

function f(a)
  fprintf('Formal parameter ''a'' is called ''%s''\n', ...
          inputname(1))
end

Answer 1

[Kaustubha Govind]

I don't think there is a MEX-API function that is the equivalent, but you can always use mexCallMATLAB to dispatch the call to MATLAB itself.

[Bård Skaflestad]

Right,

I haven't actually tested it, so I'm speculating here, but won't dispatching to, say, |inputname(n)| report the |n|-th parameter in the *caller's* parameter list (if there is such a thing) and not the |n|-th argument of the |mexFunction| parameter list?

[Bård Skaflestad]

No, it doesn't (return caller's values). This method is exactly what I'm looking for.

To give a bit of perspective, I'm trying to call an anonymous function from a MEX function. As far as I understand, function handles aren't exposed in the MEX-API and there is no equivalent of mexCallMATLAB that accepts (something akin to) a function pointer.

In my case, the function handle is stored in a structure field and the best way I could think of to achieve my goal was to dynamically form a string like

"a = s.f(rand(10))"

with |s| being the variable whose name I'd derive from 'inputname' and then to use mexEvalString (or the WithTrap variant) to affect the function call. Is there some other way?

[Jan]

You can use mexCallMATLAB to call FEVAL with the function handle as argument. Perhaps somebody knows how to use mxFevalFunctionHandle?

[Bård Skaflestad]

Ah, of course. Why didn't I think of that? The convenience of function handles means I haven't used FEVAL in probably about six years. I'd pretty much forgotten its existence...

I'll see how the FEVAL method pans out. Thanks a lot!

[Jan]

Sorry, my comment should be an answer actually.

[Kaustubha Govind]

This solution has an attached example where a function handle is passed into a MEX-function, which is then evaluated using mexCallMATLAB and feval: http://www.mathworks.com/support/solutions/en/data/1-9RKXIN/index.html - I believe this is what Jan is suggesting.

[Bård Skaflestad]

I suppose so, too. I've tried it now and it works perfectly. Thank you so much, both of you. This was really helpful.

Answer 2

[Jan]

You can use mexCallMATLAB to call FEVAL with the function handle as argument.

Perhaps somebody knows how to use mxFevalFunctionHandle?

[Bård Skaflestad]

Thank you, Jan. This is the solution I ended up using.