[Nickle] log is still (again?) deathly slow
Keith Packard
nickle@nickle.org
Sat, 23 Nov 2002 16:46:41 -0800
Around 2 o'clock on Nov 23, Bart Massey wrote:
> time nickle -e 'for (int i = 0; i < 10000; i++) log(0.05);'
The default mantissa (256) bits makes this rather slow. Try a smaller
mantissa:
$ time nickle -e 'for (int i = 0; i < 10000; i++) log(imprecise(0.05,50));'
real 0m1.511s
user 0m1.470s
sys 0m0.040s
$ time nickle -e 'for (int i = 0; i < 10000; i++) log(imprecise(0.05,100));'
real 0m8.803s
user 0m8.760s
sys 0m0.040s
Log is (currently) implemented as a polynomial kernel which yields 50 bits
and newtons method which doubles precision each time around the loop, but
that loop calls exp which is no speed daemon.
Keith Packard XFree86 Core Team HP Cambridge Research Lab