60 decimal digits of accuracy come in handy when doing computations based on the angular difference between different sides of a proton on the opposite end of the universe. :-)
----- Original Message ----- From: Ralph G Selfridge <[EMAIL PROTECTED]> Date: Thursday, December 7, 2006 7:23 am Subject: [Jgeneral] exp(y). sin(y) and accuracy. > Not too many years ago we used massive tables of logs, sin etc, in > enormous > volumes. These also gave ways ways to interpolate between entries. > > But more interestingly the tables were supposed to be 'new' but > some > enterprising types were able to show that there were errors in the > tables, > and then tracked these errors back as far as 100 years. > > There will never be a decent answer to 'precision', and those who > need it > must prepare for long run times, with their own code. But also, > over the > years, I have often seen a demand for an accuracy that is hopeless > given > the starting point of the problem (my first exposure being a > request for > results to 8 places when the original data was, at best, 4 places). > > When faced with a demand for 10^200 in computer hardware the > question can > often be 'do you really know what your problem is? and will the > final > results have any significant digits at all?' ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
