On 24 June 2013 15:05, leif <not.rea...@online.de> wrote: > John Cremona wrote: >> >> On 24 June 2013 14:21, John Cremona <john.crem...@gmail.com> wrote: >>> >>> That message is coming from mwrank. For curves with 2-torsion like >>> this is uses a 32-bit data structure to hold some information, which >>> can only handle curves with at most 31 bad primes. Yours has 37. >>> >>> When I wrote that code most machines were 32-bits so that was a >>> reasonable restriction. A quick look at the code suggests to me that >>> on a 64-bit machine that bound could be doubled. If so, mwrank could >>> handle your curve. I will test that. If it works easily then I will >>> report that here: you could patch your version of eclib (which is >>> built when Sage is built). It would take longer for the patched >>> version of eclib to get into the official Sage distribution. >> >> >> It turned out to be easy to make that patch in eclib. For your curve, >> the outcome is easy: >> >> Curve >> [0,-13617805477079302032775490621796745415629849355261725336480836,0,46361156502774656420706049081873770250935676797216145262260945858412529896278403912857919022397470373971865899207535296000,0] >> : selmer-rank = 2 >> upper bound on rank = 0 >> >> As I said above, you will have to wait until that patch is merged into >> Sage's version of eclib, sorry. >> >> Thanks for pointing this out. The code now autodetects the nummber of >> bits in an unsigned long, and that is the bound on the number of >> primes factors which can be handled. > > > Couldn't you just use uint64_t instead?
Yes, that would work and would allow 32-bit people more leeway. John > > Just asking... > > > -leif > > -- > () The ASCII Ribbon Campaign > /\ Help Cure HTML E-Mail > > > -- > You received this message because you are subscribed to the Google Groups > "sage-support" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-support+unsubscr...@googlegroups.com. > To post to this group, send email to sage-support@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-support. > For more options, visit https://groups.google.com/groups/opt_out. > > -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/groups/opt_out.
