On Sat, 15 Dec 2012, Oliver Pinter wrote:
On 12/15/12, Bruce Evans <b...@optusnet.com.au> wrote:
... Because of the different grouping of the multiplications, the second is unfortunately slower (1 more multiplication that cannot be done at compile time). The second also gives unnecessary (but findamental to the method) inaccuracy by pulling out the factor of 1000. The first gives the same inaccuracy, and now it is because the constant is not correctly rounded. It should be 2.0**64 / 10**3 = 1844674407309551.616 (exactly) = 1844674407309552 (rounded to nearest int) but is actually rounded down to a multiple of 1000. ...
mav@ already fixed the rounding before I wrote that :-). He also changed some (uint64_t)1's to use the long long abomination :-(.
Thanks for the detailed answer. :)
Bruce _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
