To use Microsoft Visual Studio .NET 2003 version 7.1, you will first need to install a patch. Unfortunately, while Visual Studio 7.1 generally produces good code, it has a performance bug in the intrinsic exp function. To get around this, edit the mex options file (C:\MATLAB6p5p1\bin\win32\mexopts\msvc71opts.bat) to read:
set OPTIMFLAGS=/MD -O2 -Oy- /Oi- -DNDEBUG
After changing the compiler, you should re-compile your mex files, and re-install any packages including mex (such as lightspeed).
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