Determine whether array represents data as signed 8-bit integers
Logical 1 (true) if the array stores its data as signed 8-bit integers, and logical 0 (false) otherwise.
Use mxIsInt8 to determine whether the specified array represents its real and imaginary data as 8-bit signed integers.
In C, calling mxIsInt8 is equivalent to calling:
mxGetClassID(pm) == mxINT8_CLASS
In Fortran, calling mxIsInt8 is equivalent to calling:
mxGetClassName(pm) .eq. 'int8'