>> I know the calculator that comes with Windows XP will produce the >> correct mathematical results. I think the Windows version 7 does the >> same. I do not have Windows 10 and therefore cannot address that >> one, if there is one. Even EXCEL spreadsheet does not do the job >> properly. So use caution with your calculations. > OK noted. The original calculations were done with a calculator that > was designed for high precision (in the floating point sense). I did > re-run the calculations in windows calculator for kicks, and the > result is different, although the difference is too small to have an > effect on the integer phase accumulator increment (fingers crossed!) >> However, with all that said, it means nothing if you cannot properly >> measure the final value against an external standard of greater >> accuracy. Acquiring the equipment to do the external measurements is >> where the real cost comes in. > Yes, I think that I am aware of that and I have the opportunity to > do that with somebody else's gear. I also understand that I'm supposed > to do that on a regular basis. >> Hopefully the above helps to clear up your query ? > Yes most of it is clear, thank you. Unfortunately though my original > question, i.e. how to incorporate the reported R value into the > calculation, is still kind of open. I'm still convinced that what I > did, i.e. not taking the R number into account, is no worse than > using it. But this might be incorrect, and if it is I'd like to know > why. > Regards and thanks again > Matt I have found a most useful and accurate calculator on the net. http://thenerdshow.com/calculator.html It's a BigNum calculator. Better yet: 1. It operates in "Floating Point" with most any number base. This is rare among calculators. Even the limited 64bit Microsoft calculator doesn't do this. 2. Standard +, -, *, /, X^N, X^(1/N) all in floating point. 3. Up to 5000 digits. redrok AD0TJ redrok@redrok.com http://www.redrok.com