MATLAB: Cpp to Mex conversion

conversioncppmex

How can I do a cpp conversion to mex?

Thanks

Best Answer

Looks like you have a mismatch with variable types, probably an older piece of code that you are trying to compile on a newer MATLAB version. E.g., the code probably has this definition:

const int *DimsBness;

when it should be this:

const mwSize *DimsBness;

And you probably have something like this:

const int *dims;

or this

int dims[] = {2,3}; /* or whatever */

when it should be this:

const mwSize *dims;

or this

mwSize dims[] = {2,3}; /* or whatever */

Simply update the code with the required types to fix these errors.

Related Solutions

MATLAB: How to convert to Mex from Cpp using Xcode ver 10

Your SegmentBoneDP.cpp file is the source code.

If you need something that converts C++ code into MATLAB code, then you are using the wrong product family. There is no known program that converts C++ code into MATLAB code.

"The point is that I don't know the number and type of inputs the function requires since I cannot open it to see it. "

You read them out of the C++ source code.

    Bness = (double *)mxGetData(prhs[0]);
    double *pF0,*pF1,*pBth,*pJumpConst;
    pF0 = (double *)mxGetData(prhs[1]);
    pF1 = (double *)mxGetData(prhs[2]);
    pBth = (double *)mxGetData(prhs[3]);
    pJumpConst = (double *)mxGetData(prhs[4]);

The first parameter is Bness, and is a 2D double array.

The second parameter is F0, and it is a double scalar. It appears to be used as a weight or smoothing factor

The third parameter is F1, and it is a double scalar. It appears to be used as a weight or smoothing factor

The fourth parameter is Bth, and it is a double scalar. It is a threshold between bone and no bone.

The fifth parameter is JumpConst, and it is a double scalar. It appears to be some kind of penalty for moving from bone to no bone.

The output is an array the same size as Bness, and it is a real double 2D array.

MATLAB: Mex error: “error C2664: ‘mxCreateNumericArray_730’ : cannot convert parameter 2 from ‘int [2]’ to ‘const size_t *'”

The signature for mxCreateNumericArray is:

mxArray *mxCreateNumericArray(mwSize ndim, const mwSize *dims, 
         mxClassID classid, mxComplexity ComplexFlag);

The macro mwSize evaluates to a specific type at compile time depending on the current settings. For your case and from the error message, this appears to be size_t. So the effective signature for your particular case is:

mxArray *mxCreateNumericArray(size_t ndim, const size_t *dims, 
         mxClassID classid, mxComplexity ComplexFlag);

And, from the error message, it appears you have maps_dim as an array of int. I.e., you have something like this in your code:

int maps_dim[2];

An int is a signed integer, probably 4 bytes on your system. A size_t is an unsigned integer, possibly 8 bytes on your system. You can't convert a pointer_to_int into a pointer_to_size_t because the underlying types are different. You need to make sure all of the pointer arguments in these function calls are exactly the same. So change your definition of maps_dim:

mwSize maps_dim[2];

Then that 2nd argument will match.

Best Answer

Related Solutions

MATLAB: How to convert to Mex from Cpp using Xcode ver 10

MATLAB: Mex error: “error C2664: ‘mxCreateN​umericArra​y_730’ : cannot convert parameter 2 from ‘int [2]’ to ‘const size_t *'”

Related Question

MATLAB: Mex error: “error C2664: ‘mxCreateNumericArray_730’ : cannot convert parameter 2 from ‘int [2]’ to ‘const size_t *'”