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Re: Possible limitaion for distance measurement
From: Herbert Prinz
Date: 2009 Mar 11, 17:30 -0400
From: Herbert Prinz
Date: 2009 Mar 11, 17:30 -0400
Hello George, The sole subject of Bremiker's article that I cited is the numerical accuracy of a given algorithm in a specific implementation (such as, say, a work sheet for Dunthorne's formula, broken down into such and such terms, evaluated by, say, 5 place logarithmic tables). In other words, if D, H, h, H' and h' are given, he asks about the potential numerical error in D' that is inherent in a given numerical procedure. This question is different from the one that investigates how D' depends analytically on D, H, h, etc. Should one find that under certain circumstances D could be nearly the same for substantially different D' (so that it becomes hard to derive D' from D), this would affect all numerical methods equally, because the limitations stem primarily from the measurement of D. Herbert Prinz George Huxtable wrote: >[...] If Herbert is discovering, in Bremiker's work, worst-case examples in which >the precision of a lunar distance is only half of what you might otherwise >expect, keep an open mind; Bremiker might be including the effects of >parallactic retardation. > > > --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
