ECo "Undefined symbols for architecture x86_64"

I'm trying to compile a mex file and I got this error:

 >> mex S-Function/coordinate_converter.cpp
Building with 'Xcode Clang++'.
Error using mex
Undefined symbols for architecture x86_64:
  "State(double, Vector const&, double)", referenced from:
      mdlOutputs(SimStruct_tag*, int) in coordinate_converter.o
  "Elements(double, Vector const&)", referenced from:
      mdlOutputs(SimStruct_tag*, int) in coordinate_converter.o
  "Vector::Vector(int)", referenced from:
      mdlOutputs(SimStruct_tag*, int) in coordinate_converter.o
  "Vector::~Vector()", referenced from:
      mdlOutputs(SimStruct_tag*, int) in coordinate_converter.o
  "Vector::operator=(Vector const&)", referenced from:
      mdlOutputs(SimStruct_tag*, int) in coordinate_converter.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

My mdlOutputs look like this:

static void mdlOutputs(SimStruct *S, int_T tid)
{

//Local variables
Vector  y_in(6);
Vector  y_out(6);

//Get parameters
real_T  *Y_IN = (real_T *) ssGetInputPortRealSignal(S, 0);
for(int_T i = 0; i < 6; i++) y_in(i) = Y_IN[i];

//Computation
if(int(*mxGetPr(ssGetSFcnParam(S, 1))) == 1)      // Cartesian > Keplerian
  y_out = Elements(GM_Earth, y_in);
else if(int(*mxGetPr(ssGetSFcnParam(S, 1))) == 2) // Keplerian > Cartesian
  y_out = State(GM_Earth, y_in, 0.0);
else
  ssSetErrorStatus(S, "Wrong parameter, should be 1 or 2");

real_T  *Y_OUT = ssGetOutputPortRealSignal(S, 0); //Output
for(int_T i = 0; i < 6; i++) Y_OUT[i] = y_out(i);
}

I would really appreciate if you could help me with this. Thank you so much.

[Walter Roberson]

You specifically call upon State and Elements in the code: what are you expecting those to be?

Answer 1

[Sainath Varikuti]

Hi,

When performing mex, you have to include the source file with elements and state methods. You may refer to the following documentation page.

http://www.mathworks.com/help/simulink/sfg/example-using-s-functions-to-incorporate-legacy-c-code.html

Regards, Sainath