[Jprogramming] J and Group Theory

[Kenneth Lettow]

Is this what you need?

   #:i.4
0 0
0 1
1 0
1 1
   'a b c d'=: #:i.4
   a
0 0
   b
0 1
   c
1 0
   d
1 1


On Wed, Dec 11, 2013 at 11:36 AM, Jon Hough <jghough at outlook.com> wrote:

> Hi,
>
>
> I saw in the J labs the example for the group Z_4 (cyclic group of order
> 4).
>
>
>
> I am now trying to ape this method to create the group Z_2 x Z_2 (direct
> product of cyclic group order 2 with itself).
>
> This is what I have done so far:
>
>
>    a =: 0 0
>    b =: 0 1
>    c =: 1 0
>    d =: 1 1
>
>
>  f =: 2&|@+
>
>
> This is the group operator, essentially mod 2 addition.
>
> Q: How can I create a,b,c,d more simply? Perhaps with a single verb,
> instead of explicitly creating each element?
>
>
>
> e.g. a verb or train that returns:
> 0 0
> 0 1
> 1 0
> 1 1
>
> Thanks for your patience.
>
> Jon
>
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>



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