[Jprogramming] Tessellations

[Brian Schott]

I am working with dyadic tessellations using `tesl` below. There are 2
versions that give different results: "tacit" and "explicit" . The
"explicit" version works well for me, but I cannot duplicate the results
with the "tacit" format.

So, I am wondering if anyone can tease the "tacit" format into the desired
result?

Notice that the shapes of both "filters" and "image" are prefixed with 3's
and as a result the shape of the result reflects the 3 separate
tessellations.  But my "tacit" version has an extra 3-shaped dimension in
resulting shape.

   tesl =: ;._3
   link =: ;
   cntrl =: 1 1,:2 2
   filters =: 10+i.3 2 2 2
   image =: 3 3 3$'abcdefghi','ABCDEFGHI',|.'abcdefghi'
   $cntrl filters&(link"2) tesl"3 2 image NB. "tacit"
3 2 2 3 2 2
   $filters(4 : 'cntrl x&(link"2) tesl y')"3 2 image NB. "explicit"
3 2 2 2 2


(Btw, I have been using a trick to economize on the vertical space needed
to screen-print the results in my experiments. An alternative to prefixing
the expressions with "$" as in the expressions below, I have found that the
prefix ",." can be quite effective.)

Thanks,

-- 
(B=)