There is only one entry point to a mex file, the mexFunction, which
transmits the passed-in arguments to the C++ side.
To support multiple functions, PastelMatlab defines the mexFunction in
such a way that the first parameter is assumed to be a string which
specifies the actual function name to call inside the mex file. On call,
PastelMatlab redirects to the correct function, with the remaining
parameters transmitted as they are. These functions are registered
callable by the functions found here.