I need to make dll file for computing user defined function in Lindo Lingo. I need to implement two new functions, but I can make only one myuser.dll file for use in Lingo.

But, talking with people from Lindo, it is possible to make two argument myuser.dll function, with first first argument as a "branching" variable. for example, For example,

@USER( 1, 2.4)

might compute the sin of 2.4, while

@USER( 2, 2.4)

would compute the cosine of 2.4. The first argument of 1 implies return the sin, while a first argument of 2 implies return the cosine.

My question is how to do that, because I am new to Vc++.

Thanks in advance,

Aleksandar