Settlement Date and NPV Date parameters for Cashflows.Yield method

Posted by MichaelKnox on Aug 31, 2016; 10:31am
URL: http://quantlib.414.s1.nabble.com/Settlement-Date-and-NPV-Date-parameters-for-Cashflows-Yield-method-tp17679.html

I'm calculating IRR for a list of cashflows (both actual historic cashflows and projected future cashflows) and I'm a little confused by the purpose of the settlementDate and npvDate parameters.  I'm using the c# QLNet library, but this seems a more appropriate place to post since the code is nearly the same and this forum appears to be much more responsive.

I know that any cashflow before the settlementDate are excluded, but can someone give me a good definition of these two parameters?

Thanks