Incomplete GMP documentation...
tg at swox.com
Tue Sep 19 12:18:10 CEST 2006
Looking through the GMP mailing list archives, I found an odd
reply from myself:
Torbjorn Granlund <tege at swox.com> writes:
I believe mpz_root can be speeded up; I might look into it if I get
some spare time.
Yes, http://swox.com/gmp/projects.html suggests a division-free
x = x (3 A x )/2
i+1 i i
This should be faster than the current code, since division is hard to
make fast (and since current GMP division is a log(n) factor worse
I replied as if you talked about mpz_sqrt/mpn_sqrt, not mpz_root.
I try again: Please look at http://swox.com/gmp/devel/ for vastly
improved nth root code. Compared to the code in GMP 4.2, there
is a 20x to 30x speedup.
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