Thanks, fixed now. The code dates from the time when x. was the left argument.
On Thu, Feb 4, 2021 at 4:00 PM 'Michael Day' via Programming <programm...@jsoftware.com> wrote: > > Having a look at the scripts in ~addons/math/misc, I've just noticed a > slip in > fermat.ijs - I doubt if it's used much, though, which is probably why > it hasn't > been reported. Its fellow script, pollard.ijs, has a greatly superior > factoring > algorithm or two. > > The optional left argument of the verb fermatfactor specifies the maximum > number of iterations, but on starting the dyad, x is immediately > replaced by > the ceiling of the square root of y. > > These few lines will cure the problem, with a variable name to taste; > I'm using > X here. > > fermatfactor=: 3 : 0 > 10000 fermatfactor y > : > X=. >.@%: x: y NB. perhaps call it rty for sqrt y > u=. >:+:X > v=. 1 > r=. (*:X)-y > NB. the rest is ok > > The problem is there in J902 as well as J903 beta, and presumably in > earlier versions too. > > Cheers, > > Mike > > -- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
