mex files link error

i use matlab 2013 x32 and visual studio 2008 sp1 but every time i get this fatal error.

LINK : error LNK2001: unresolved external symbol mexFunction 
...mex_ZIBcNM\templib.x : fatal error LNK1120: 1 unresolved externals 

D:\MATLAB\R2013A\BIN\MEX.PL: Error: Link of 'libqp_gsmo.mexw32' failed.

[Geoff Hayes]

Merve - please provide some context surrounding this error. What are you executing that result in this error message? If you are building a MEX file from the Command Window, then please include this statement.

Answer 1

[merve]

i reinstall matlab R2013a x64 (because my machine is x64) and install sdk 7.1(to do this remove all .net frameworks,sdk versions and any runtimes firstly).

then in the "mex-setup" i choose sdk7.1 (it is "[1] Microsoft Software Development Kit (SDK) 7.1 in C:\Program Files (x86)\Microsoft Visual Studio 10.0 " ).

in my folder i have two different source code: my pure c code(the function) and my mex function. i move this mex function into pure c code function.(do not forget to add #include "mex.h") and then It Works!

thanks for all answers and comments....

Answer 2

[Jan]

Does your source file contain a mexFunction definition?

[merve]

ok i have to explain more detailed; actually i get some source files that i know that works fine and (i must change some part of these files) but firstly i just try to run these workin files on matlab. there is no incompatibility with the compiler because it works with another examples in matlab.

it contain a mexFunction definition in source file in libqp_gsmo_mex.c.

#include "mex.h"
#include "string.h"
#include "libqp_gsmo.c"

#define LIBQP_MATLAB
#include "libqp.h"

#define INDEX(ROW,COL,NUM_ROWS) ((COL*NUM_ROWS)+ROW)
#define MIN(A,B) ((A < B) ? A : B)
#define MAX(A,B) ((A > B) ? A : B)

double *mat_H;
uint32_t nVar;

const double *get_col( uint32_t i )
{
  return( &mat_H[ nVar*i ] );
}

void mexFunction( int nlhs, mxArray *plhs[],int nrhs, const mxArray*prhs[] )
{
  int verb;          
  uint32_t i;         
  uint32_t MaxIter;   
  double TolKKT; 
  double *vec_x;         /* output arg -- solution*/ 
  double *vec_x0;         
  double *diag_H;    /* diagonal of matrix H */
  double *f;         /* vector f */
  double *a;
  double b;
  double *LB;
  double *UB;
  double fval;
  libqp_state_T state;
  /*------------------------------------------------------------------- */
  /* Take input arguments                                               */
  /*------------------------------------------------------------------- */

    if( nrhs != 10) mexErrMsgTxt("Incorrect number of input arguments.");

    mat_H = mxGetPr(prhs[0]);
    nVar = mxGetM(prhs[0]);
    f = mxGetPr(prhs[1]);   
    a = mxGetPr(prhs[2]);
    b = mxGetScalar(prhs[3]);
    LB = mxGetPr(prhs[4]);
    UB = mxGetPr(prhs[5]);
    vec_x0 = mxGetPr(prhs[6]);
    MaxIter = mxIsInf( mxGetScalar(prhs[7])) ? INT_MAX : (long)mxGetScalar(prhs[7]);
    TolKKT = mxGetScalar(prhs[8]); 
    verb = (int)(mxGetScalar(prhs[9])); 

    if( verb > 0 ) {
      mexPrintf("Settings of QP solver\n");
      mexPrintf("MaxIter : %d\n", MaxIter );
      mexPrintf("TolKKT  : %f\n", TolKKT );
      mexPrintf("nVar    : %d\n", nVar );
      mexPrintf("verb    : %d\n", verb );
    }

    plhs[0] = mxCreateDoubleMatrix(nVar,1,mxREAL);
    vec_x = mxGetPr(plhs[0]);
    memcpy( vec_x, vec_x0, sizeof(double)*nVar );

    diag_H = mxCalloc(nVar, sizeof(double));
    if( diag_H == NULL ) mexErrMsgTxt("Not enough memory.");
    for(i = 0; i < nVar; i++ ) 
      diag_H[i] = mat_H[nVar*i+i];

    /*------------------------------------------------------------------- */
    /* Call QP solver                                                     */
    /*------------------------------------------------------------------- */

    state = libqp_gsmo_solver( &get_col, diag_H, f, a, b, LB, UB, vec_x, 
                          nVar, MaxIter, TolKKT, NULL );

    /*------------------------------------------------------------------- */
    /* Generate outputs                                                   */
    /*------------------------------------------------------------------- */

    plhs[1] = mxCreateDoubleScalar(state.QP);
    plhs[2] = mxCreateDoubleScalar((double)state.exitflag);
    plhs[3] = mxCreateDoubleScalar((double)state.nIter);

    /*------------------------------------------------------------------- */
    /* Clean up                                                           */
    /*------------------------------------------------------------------- */
    mxFree( diag_H );
  }

/* EOF */

    if true
      % code
    end

[Titus Edelhofer]

Hi Merve,

I hope the missing space in

const mxArray*prhs[]

is copy paste error?

Titus

[Titus Edelhofer]

Hi Merve,

I just tried your function (commenting out all libqp stuff). Worked fine. Please compile using "-v" to see if something else went wrong before ...

Titus

[merve]

after compiling -v it says; Contents of C:\Users\lenovo\AppData\Local\Temp\mex_7Jd3gr\mex_tmp.rsp: C:\Users\lenovo\AppData\Local\Temp\mex_7Jd3gr\libqp_gsmo.obj

.obj file is in my current folder on matlab but it is not exist in C:\Users\lenovo\AppData\Local\Temp\mex_7Jd3gr\

thanks for help

[Titus Edelhofer]

In this case you should (re-)run "mex -setup" to configure the mex options.

Titus