Well, if we can agree that (-<.) -: 1&| , then these rules are already
proving inconsistent.

   1 | 0.6j0.6
_0.4j_0.4
   (-<.) 0.6j0.6
_0.4j0.6

Here is the model I'm currently aiming for:
1&| for reals is defined as the function which shifts by an integer such
that (0<:1&|) and (1>1&|)
1&|  -:  1&|&.+.
b&|  -:  1&|&.(%&b)
<.  -:  (- 1&|)
($0)&#:  -:  ($0)"_
(bs,b)&#:  -:  ((bs #: <.@%&b),b&|)    NB. bs a list, b a scalar

These definitions are consistent with current definitions for real numbers
and provide a very natural extension to complex numbers. Furthermore they
have the desirable property that <.@:(-&0.5j0.5) gives the nearest complex
number to the argument. However, they're still up for revision if someone
can convince me either that the current definition of <. makes sense or
that the current definitions are used in important code that would break
under this remodeling.

Marshall

On Sun, Jan 22, 2012 at 12:49 PM, Don Guinn <dongu...@gmail.com> wrote:

> The thing is that floor, ceiling, residue and antibase are related and all
> should be handled by the same rules, whatever they may be.
>
> On Sun, Jan 22, 2012 at 10:38 AM, Marshall Lochbaum <mwlochb...@gmail.com
> >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
> > > >>
> > > >
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