You can do this with a helper m-file:
% CreateClassArray.m helper file for mxCreateClassArray mex function
function class_array = CreateClassArray(dims,classname)
estring = 'class_array(';
for k=1:numel(dims);
estring = [estring '1:' num2str(dims(k)) ','];
end
estring(end) = ')';
estring = [estring '=' classname ';'];
eval(estring);
end
And then you can use this function in your mex routine:
/* Create a class array with default class element entries */
mxArray *mxCreateClassArray(mwSize ndim, const mwSize *dims, const char *classname)
{
mxArray *rhs[2];
mxArray *mx, *mxtrap;
mwSize i;
double *pr;
rhs[0] = mxCreateDoubleMatrix(1, ndim, mxREAL);
pr = mxGetPr(rhs[0]);
for( i=0; i<ndim; i++ ) {
pr[i] = dims[i];
}
rhs[1] = mxCreateString(classname);
if( mxtrap = mexCallMATLABWithTrap(1,&mx,2,rhs,"CreateClassArray") ) {
mxDestroyArray(mxtrap);
mx = NULL;
}
mxDestroyArray(rhs[1]);
mxDestroyArray(rhs[0]);
return mx;
}
Caution: The above is bare bones with NO ARGUMENT CHECKING. I will clean this up with more comments and put in argument checking and post to the FEX in the near future. Also, the above assumes R2008b or later. For R2008a there is no mexCallMATLABWithTrap function in the API. In that case download the FEX submission noted below for mxGetPropertyPtr and there is a replacement mexCallMATLABWithTrap function included.
You might also be interested in this FEX submission for getting the mxArray pointers to class element properties:
