On Mon, Feb 15, 2010 at 3:09 PM, François Bissey <f.r.bis...@massey.ac.nz> wrote: > On Tue, 16 Feb 2010 10:40:11 William Stein wrote: >> > sage -t "devel/sage/doc/en/tutorial/tour_numtheory.rst" >> > ********************************************************************** >> > File "/opt/sage/devel/sage/doc/en/tutorial/tour_numtheory.rst", line 94: >> > sage: x = crt(2, 1, 3, 5); x >> > Expected: >> > -4 >> > Got: >> > 11 >> >> The above two are because you are using GMP instead of MPIR. >> > So you are saying we need to link against the mpir version of the gmp > libraries and that linking against gmp ones produces this result.
If you link against mpir then the above discrepancy would go away. However, i can also tell you that the above discrepancy is harmless. The issue is simply that both answers are right. e.g., the line sage: x = crt(2, 1, 3, 5); x uses the Chinese Remainder Theorem to find an integer x such that x % 3 == 2 and x%5 == 1. Both -4 and 11 are correct choices of x. The other related tests involving "modular symbols" are different because of the same function. > I guess a finer point to know is. is this result correct but not reduce to > same domain? And does it have nasty consequences later - ie do > other thing rely on the result to be in this domain? No, there is definitely no nasty consequence. > One more question, if we need to link against mpir's libgmp, does linking > sage itself against it enough, or do we need to also link pari, mpfr, mpfi > and other against it as well? mpfr in itself would be a problem as it is > part of the toolchain (gcc is compiled against it). I think linking sage itself is likely to be enough for doctests to pass, though it is hard to be sure. It would be nice to link pari too. William > > Francois > > -- > To post to this group, send an email to sage-devel@googlegroups.com > To unsubscribe from this group, send an email to > sage-devel+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
