MATLAB: Use matrix c\c++ API with row-based indexing

cMATLAB

Hi all, in my project I perform some calculations in c++, and then I am using Matrix API (mxCreateNumericArray) to save my 2D array into .mat file. In c++ I work with native row-based indexing, however Matlab functions assume column-based order. Is there an option to quickly fix this? I can convert row-based to column based, but don't want to do this (for greater performance). Btw, my array is not symmetric. Here is a piece of c++ code:
        const mwSize dims[] = { M1, M2 };
  mxArray *pa1 = mxCreateNumericArray(2, dims, mxSINGLE_CLASS, mxREAL);
  
  memcpy((void *)(mxGetPr(pa1)), (void *)iu_cpu, M1*M2*sizeof(float));
  matPutVariable(pmat, "LocalDouble", pa1);
  mxDestroyArray(pa1);
So, iu_cpu is 1D array representing 2D matrix in row-based order. And matlab 2D array pa1 is obtained from iu_cpu assuming column-based order.
Here is simple example: Imagine I have matrix
   a={1 2 3
      4 5 6
      7 8 9
      10 11 12}
Then, iu_cpu={1,2,3,4,5,6,7,8,9,10,11,12}. However array pa1 will be obtained from iu_cpu assuming column-major order: pa1={1,4,7,10,2,5,8,11,3,6,9,12}
Update: Following the advice of James Tursa, I tried to use mexCallMATLAB. For some reason, Unhandled expression:access violation error appears when I am tring to call this function. Here is full code:
    #include "mat.h"
    #include "iostream"
    #include "mex.h"
    int main(){
  float data[9] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 };
  MATFile *pmat = matOpen("mattest.mat", "w");
  const mwSize dims[] = { 3, 3 };
  mxArray *pa1 = mxCreateNumericArray(2, dims, mxSINGLE_CLASS, mxREAL);
  mxArray *pa1T;
  memcpy((void *)(mxGetPr(pa1)), (void *)data, 3 * 3 * sizeof(float));
  
  
  mexCallMATLAB(0, NULL, 1, &pa1, "disp");
  mexCallMATLAB(1, &pa1T, 1, &pa1, "transpose");
  
  
  matPutVariable(pmat, "LocalDouble", pa1T);
  mxDestroyArray(pa1);
  mxDestroyArray(pa1T);
    }
Even simple mexCallMATLAB(0, NULL, 1, &pa1, "disp"); causes this error. May be I didn't add something to my project? Even this sample code http://www.mathworks.com/help/matlab/apiref/rmvd_matlablink__4f95060e6fdb200c8b9414502f277cc0.html doesn't work(unresolved external symbol)
Update 2: Full output:
    1>------ Build started: Project: wrtie_mat, Configuration: Debug x64 ------
    1>  Source.cpp
    1>MSVCRTD.lib(crtexe.obj) : error LNK2019: unresolved external symbol main referenced in function __tmainCRTStartup
    1>C:\programs\misha\cuda\Projects\test projects\wrtie_mat\x64\Debug\wrtie_mat.exe     : fatal error LNK1120: 1 unresolved externals
    ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
When I tried to compile in matlab (mex Source.cpp), there was also error:
Unable to complete successfully.

Best Answer

You could transpose it after loading the mat file. Or you could call MATLAB to transpose it for you prior to saving the variable to a mat file. E.g.,
mxArray *pa1T;
mexCallMATLAB(1, &pa1T, 1, &pa1, "transpose");
matPutVariable(pmat, "LocalDouble", pa1T);
mxDestroyArray(pa1T);
mxDestroyArray(pa1);
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