Although I am a fairly experienced Fortran programmer, I have little or no idea about how to create a Fortran DLL that can be subsequently used in MS Excel. Browsing the DVF and Excel documentation also doesn't seem to get me anywhere, so I hope that one of you will be able to point me in the right direction.

For the sake of discussion, suppose I want to create a library with my own Fortran functions and make it available within Excel. In fact, let's assume the library will contain only two simple functions, say:

Real Function MySub1 (a, b, c)

Implicit None

Real, Intent (IN) :: a, b, c

Real :: MySub2

MySub1 = a + MySub2 (b, c)

Return

End Function MySub1

Real Function MySub2 (b, c)

Implicit None

Real, Intent (IN) :: b, c

MySub2 = b * c

Return

End Function MySub2

My questions are as follows:

1) How do I go about creating the DLL? Is it as simple as creating a new DLL project in DVF and then compiling and linking? Or do I need to take any special measures.

2) Once the DLL has been successfully created, how can I make it available for use in MS Excel, so that, for example, I can use formulas like "=MySub1(A1,A2,A3)" or "=MySub2(B1,B2)" in a spreadsheet cell?

Thanks in advance for your feedback!