I wanted to take 'mod' of the real part and leave the imaginary part untouched. f=:(|9&o.)+j.&(11&o.)&] 7 f 73j73+i.6 3j73 4j73 5j73 6j73 0j73 1j73 Perhaps this is not done by a complex '|' ?
>________________________________ > Fra: Marshall Lochbaum <mwlochb...@gmail.com> >Til: Programming forum <programming@jsoftware.com> >Sendt: 19:50 søndag den 22. januar 2012 >Emne: Re: [Jprogramming] 5|0 1 2 3 4 is not equal to 5|0 1 2 3 4 j.0 > >It would be possible to change complex mod without changing floor. Floor is >consistent on reals and complex numbers, while complex mod is not, so it >doesn't necessarily need to be fixed. > >The problem with complex mod is that for left argument b it that it ensures >that the result is in the box defined by corners -:(j./~ _0.5 0.5)*b . That >means that it subtracts the closest Gaussian integer multiple of b from the >right argument. This is inconsistent with mod for the reals, which >subtracts the floor under division by b. > >Marshall > >On Sun, Jan 22, 2012 at 1:28 PM, Henry Rich <henryhr...@nc.rr.com> wrote: > >> Well, I know complex floor was something Gene McDonnell was proud of, >> and I expect it's embedded in some applications. You'll need to produce >> a compelling argument for changing it. >> >> Henry Rich >> >> On 1/22/2012 12:38 PM, Marshall Lochbaum wrote: >> > I'm pretty sure I understand the definition, but I still don't get the >> > rationale. Under my scheme the "obvious" complex floor would be (- 1&|), >> > which also has the properties of convexity, translatability, and >> > compatibility listed in the dictionary. >> > >> > Marshall >> > >> > On Sun, Jan 22, 2012 at 12:08 PM, Henry Rich<henryhr...@nc.rr.com> >> wrote: >> > >> >> As Don said, make sure you understand complex floor before you start >> >> coding. >> >> >> >> Henry Rich >> >> >> >> On 1/22/2012 11:38 AM, Marshall Lochbaum wrote: >> >>> The theory of moduli is based on the quotient group of the integers by >> a >> >>> subgroup. For instance, the integers (mod 2) are produced by taking all >> >> the >> >>> integers and identifying all the ones that are even, as well as all the >> >>> ones that are odd. Then we get a two-element group which we can preform >> >>> addition on: even+even=even, even+odd=odd, etc. >> >>> >> >>> To reduce a number in a particular modulus, we need to find a canonical >> >>> representation for that number. For positive numbers n the choice is >> >> fairly >> >>> simple: n|l gives the l' such that 0<=l'<n. In the complex plane, a >> >> number >> >>> generates a grid by taking its product with the Gaussian integers; try >> >>> 'dot; pensize 2' plot , 1j2 * j./~i:10 >> >>> to see what I mean. Then what we want is a canonical form for what >> >> happens >> >>> when we identify all those points together. We're allowed to "shift" by >> >> any >> >>> Gaussian integer times the modulus. >> >>> >> >>> Based on this, I think a good way to calculate the modulus is to get >> the >> >>> number into the square that lies counterclockwise of the modulus >> number. >> >>> Practically, this means we decompose a complex number y into (a j.b)*x, >> >> and >> >>> then return (1|a)j.(1|b) . >> >>> >> >>> I'll see if I can get around to editing this. I have a working copy of >> >> the >> >>> source, but I haven't made sense of it entirely. >> >>> >> >>> Marshall >> >>> >> >>> On Sun, Jan 22, 2012 at 10:45 AM, Raul Miller<rauldmil...@gmail.com> >> >> wrote: >> >>> >> >>>> Yes, this is a bug. >> >>>> >> >>>> Someone should fix it. >> >>>> >> >>>> J is open source. (Though distributed sources do not compile for me, >> >>>> and I keep getting sidetracked when I investigate forks that might >> >>>> compile.) >> >>>> >> >>>> -- >> >>>> Raul >> >>>> ---------------------------------------------------------------------- >> >>>> For information about J forums see >> http://www.jsoftware.com/forums.htm >> >>>> >> >>> ---------------------------------------------------------------------- >> >>> For information about J forums see http://www.jsoftware.com/forums.htm >> >>> >> >> ---------------------------------------------------------------------- >> >> For information about J forums see http://www.jsoftware.com/forums.htm >> >> >> > ---------------------------------------------------------------------- >> > For information about J forums see http://www.jsoftware.com/forums.htm >> > >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> >---------------------------------------------------------------------- >For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
