Op 2005-11-20, Roy Smith schreef <[EMAIL PROTECTED]>: > [EMAIL PROTECTED] (David M. Cooke) wrote: > >> One example I can think of is a large number of float constants used >> for some math routine. In that case they usually be a full 16 or 17 >> digits. It'd be handy in that case to split into smaller groups to >> make it easier to match with tables where these constants may come >> from. Ex: >> >> def sinxx(x): >> "computes sin x/x for 0 <= x <= pi/2 to 2e-9" >> a2 = -0.16666 66664 >> a4 = 0.00833 33315 >> a6 = -0.00019 84090 >> a8 = 0.00000 27526 >> a10= -0.00000 00239 >> x2 = x**2 >> return 1. + x2*(a2 + x2*(a4 + x2*(a6 + x2*(a8 + x2*a10)))) >> >> (or least that's what I like to write). Now, if I were going to higher >> precision, I'd have more digits of course. > > You have described, if memory serves, a Taylor series, and those > coefficients are 1/3!, 1/5!, 1/7!, etc.
Well if you had infinite precision numbers you might be right. However in numerial analysis, one often uses numbers which are slightly different, in order to have a more uniform error spread over the interval used. -- Antoon Pardon -- http://mail.python.org/mailman/listinfo/python-list