MATLAB: Accessing handle graphics from within Fortran mexfunction

fortranhandle graphics

Can you access Matlab's handle graphics from within a Fortran mexFunction? I see that there are mexSet and mexGet functions; however, they appear to apply only for C mexFunctions.

Thanks a million, Bill

Best Answer

Hi Otis,

I guess (!) the answer is yes. Handles itself are just usual doubles. Therefore you should be able to call the set and get by something like

mxArray* pprhs[3];
pprhs[0] = prhs[0]; // assuming prhs[0] is the handle
pprhs[1] = mxCreateString("tag");
pprhs[2] = mxCreateString("Bill");
mexCallMATLAB(0, plhs, 3, pprhs, "set");

Titus

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#include <fintrf.h>
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C Gateway routine
C
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The main problem is that you, the programmer, need to create the output mxArray plhs(1). When you run the mex routine the only mxArray variables you start with are the prhs(etc) variables. At that point in the code, prhs(1) is unallocated. MATLAB does not create the plhs(etc) outputs for you since it does not know what the output is supposed to be ... that is your job as the programmer. Also, you should check that the inputs are int64 type before you use them that way. E.g.,

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            call mexErrMsgTxt("Need 2 inputs and at most 1 output")
          endif
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          endif
          if( mxGetNumberOfElements(prhs(1)) /= 1 .or.
       &      mxGetNumberOfElements(prhs(2)) /= 1 ) then
            call mexErrMsgTxt("Inputs must be scalar")
          endif
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          c = a + b
          return
          end

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