Burton,
Reference the Microsoft.VisualBasic.dll.
The IRR function is in the Microsoft.VisualBasic.Financial class. Remember
that Modules in VB.NET are simply classes to C# with only static members.
Something like:
double[] valueArray = { -70000, 22000, 25000, 28000, 31000 };
double irr, guess = 0.1;
irr = Microsoft.VisualBasic.Financial.IRR(ref valueArray, guess);
Debug.WriteLine(irr.ToString("P"), "irr");
I'm really not sure why they defined the valueArray to be ref, I suspect
they translated the function literally from VB6. Rather then the intent of
the function.
Hope this helps
Jay