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    Re: Computing tables
    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
    

       
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