MATLAB: How to typecast an mwArray to a C++ scalar variable

cc2440castconversiondoubleintegerlibraryMATLAB C/C++ Math Librarymwarrayoperatortypecast

How do I typecast an mwArray to a C++ scalar variable?
The methods for Extracting Data from an mwArray on page 3-41 of the MATLAB C++ Math Library User's Guide does not seem to work. I added the following code fragment to ex2.cpp at line 24:
mwArray U, S, V;
int32 i;
U=4;
i=U;
and I got the following error messages:
 C:\programs\matlabR12\extern\include\cpp\stdexcpt.h(24) : warning C4273: 'strdup' : inconsistent dll
 linkage.  dllexport assumed.
 ex2_2.cpp(30) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type
 'class mwArray' (or there is no acceptable conversion)
 MBUILD.BAT: Error: Compile of 'ex2_2.cpp' failed.

Best Answer

There is an error in the MATLAB C++ Math Library User's Guide 2.1 regarding implicit and explicit typecasting. The following codes illustrate how to correctly cast an mwArray to a C++ scalar variable:
int32 i;
double j;
mwArray A = 5;
mwArray B = 25.97;
i = A.Int();
j = B.Double();
This error in the MATLAB C++ Math Library User's Guide will be corrected for the next release of the guide.
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