On Sun, Feb 14, 2010 at 5:49 AM, Ian Clark <earthspo...@googlemail.com> wrote:
> 1. If I have a M-by-N table with entries like this
> ...
> {.  curlylfdot
>
> {:: curlylfcoco {:  curlylfco
> }   curlyrt
> ...
>
> how do I neatly slice off the first 3 columns (say) into a boxed list
> of tally M to serve as a lookup index?

In this case, you could cheat by

   st=: 0 :0
{.  curlylfdot
{:  curlylfco
{:: curlylfcoco
}   curlyrt
)
   ]li=: <;._2 st
+--------------+-------------+---------------+-----------+
|{.  curlylfdot|{:  curlylfco|{:: curlylfcoco|}   curlyrt|
+--------------+-------------+---------------+-----------+
   ]wo=: ;:&> li
+---+-----------+
|{. |curlylfdot |
+---+-----------+
|{: |curlylfco  |
+---+-----------+
|{::|curlylfcoco|
+---+-----------+
|}  |curlyrt    |
+---+-----------+

If you really want to use a fixed width first column, then try

   ]wo=: 3 ({.;}.)&> li
+---+------------+
|{. | curlylfdot |
+---+------------+
|{: | curlylfco  |
+---+------------+
|{::| curlylfcoco|
+---+------------+
|}  | curlyrt    |
+---+------------+

Ambrus
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