Closed GoogleCodeExporter closed 8 years ago
I can reproduce the problem; e.g.:
$ python -mtimeit -s'from gmpy import mpz; a=10**5000' 'x=mpz(a)'
1000 loops, best of 3: 1.14 msec per loop
$ python -mtimeit -s'from gmpy import mpz; a=10**5000' 'x=mpz("%x"%a, 16)'
10000 loops, best of 3: 107 usec per loop
$ python -mtimeit -s'from gmpy import mpz; a=10**500' 'x=mpz(a)'
10000 loops, best of 3: 21.2 usec per loop
$ python -mtimeit -s'from gmpy import mpz; a=10**500' 'x=mpz("%x"%a, 16)'
100000 loops, best of 3: 16.2 usec per loop
So the direct construction from long appears to be degrading worse-than-O(N).
Haven't had time to
examine the sources to find out why that is so, but look forward to doing so --
thaks!
Original comment by alea...@gmail.com
on 23 Jul 2008 at 11:51
I've fixed long2mpz by using the GMP function mpz_import. It is much faster.
I'm
still working updating mpz2long to use mpz_export. I'll try to get a patch in
the
next couple of days.
casevh
Original comment by casevh
on 30 Jul 2008 at 6:27
Committed r37 to improve performance.
Before:
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**500'
'x=mpz(a)'
100000 loops, best of 3: 7.25 usec per loop
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**5000'
'x=mpz(a)'
1000 loops, best of 3: 270 usec per loop
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**50000'
'x=mpz(a)'
10 loops, best of 3: 22.7 msec per loop
After:
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**500'
'x=mpz(a)'
1000000 loops, best of 3: 1.05 usec per loop
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**5000'
'x=mpz(a)'
100000 loops, best of 3: 8.67 usec per loop
case@hp2:~/svn/gmpy$ py25 -mtimeit -s'from gmpy import mpz; a=10**50000'
'x=mpz(a)'
10000 loops, best of 3: 85.2 usec per loop
Thanks for report.
casevh
Original comment by casevh
on 1 Aug 2008 at 4:48
Original issue reported on code.google.com by
fredrik....@gmail.com
on 23 Jul 2008 at 9:18