Subject: Confused about rank and append
From: richard.levine@canrem.com (Richard Levine)
Date: Tue, 20 Jun 95 16:04:00 -0500
Organization: CRS Online  (Toronto, Ontario)

I would like to add to the discussion of "difficulties with
rank" by discussing the following simple examples, the rules
of which I do not completely understand.  They, of course,
seem intuitively correct and "natural", but the precise
rules escape me.

The examples involve the "append" verb ( , ) and the "rank"
conjunction.

There must be some interaction between the definition of
"append" and the action of the rank conjunction which I am
not understanding. Is there anyone who has a moment to
provide some insight into this matter?

Example A
      (i. 2 3 4),"1 0 (1)
 0  1  2  3 1
 4  5  6  7 1
 8  9 10 11 1

12 13 14 15 1
16 17 18 19 1
20 21 22 23 1

Example B
??? This is the part that needs some explaining
although it looks OK.
Why does (1) go to the items in the first plane, and (2) to
the items in the second plane?

      (i. 2 3 4),"1 0 (1 2)
 0  1  2  3 1
 4  5  6  7 1
 8  9 10 11 1

12 13 14 15 2
16 17 18 19 2
20 21 22 23 2

Example C
      (i. 2 3 4),"1 0 (i. 2 3 )
 0  1  2  3 0
 4  5  6  7 1
 8  9 10 11 2

12 13 14 15 3
16 17 18 19 4
20 21 22 23 5

Example D
Compare with the previous expression

      (i. 2 3 4),"1 0 (i. 6)
|length error
|   (i.2 3 4)    ,"1 0(i.6)

The dictionary states:

x,y appends items of y to items of x after
1) reshaping an atomic argument to the shape of the items of
the other.

2) bringing the arguments to a common rank (of at least 1)
by repeatedly _itemizing_ ( monadic ,: ) any of lower rank,
and

3) bringing them to a common shape by padding with fill
elements in the manner described in Section II B.

Rule 2) seems to be involved in Examples B and C, but are
rules 1 to 3 are being applied before or after the
application of the rank conjunction ??

Thanks in advance for any help on this matter.

--signed (confused about rank and append)
RL
