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Re: Computing tables
From: Tony S
Date: 1999 Sep 09, 11:28 PM
From: Tony S
Date: 1999 Sep 09, 11:28 PM
"Richard B. Emerson" wrote: > > Well, it's possible to compute results accurate to many places even > though the native word size may be limited. There are some excellent > integer routines around, too, which offer speed advantages. The point > here is that a 32 bit processor can give good, long results *if you're > willing to wait for them*. No argument there. The wait time can be considerable. The source data from either USNO or HMNO really is not a limiting factor in 32 bit. It could well be in resolving sin/cos functions in less precise formulae. > My question is directed towards knowing > just how accurate the tables are in terms of identifying systematic > errors (e.g., rounding errors which propigate forward through a > series). This would be academically interesting but of little practical value in marine navigation, IMO. In any event, I'll leave that to the math heads at JPL/NASA/DOD who may have greater needs. :-) Tony