Lovely. Tiny remark:
-.@+. could be replaced by +:
On 1/26/2015 1:00 AM, Raul Miller wrote:
A note of explanation...
(I have been noticing that far too much software is poorly documented.
And while I cannot do an adequate job of documenting other people's
software, I can document software I write.)
F=: </.~ +/\@(-.@+._1&|.)@:=&(<,'&')
T=: ;:'4&count int 3 8&inrange'
The first thing I do is find out where & appears:
=&(<,'&') T
0 1 0 0 0 1 0
The second thing I do is rotate to the right and combine:
(+. _1&|.) =&(<,'&') T
0 1 1 0 0 1 1
Except I want to mark the beginning of each section with a 1, and
right now they are zeros.
(-.@+. _1&|.) =&(<,'&') T
1 0 0 1 1 0 0
As an aside, note that I could have cut that step out if I had started
by identifying where & does not appear (and then combine using logical
and instead of logical or):
(* _1&|.) ~:&(<,'&') T
1 0 0 1 1 0 0
Next, I use plus scan to turn my markers into keys:
+/\ (* _1&|.) ~:&(<,'&') T
1 1 1 2 3 3 3
Finally, I use these keys to group the original elements:
T </.~ +/\ (* _1&|.) ~:&(<,'&') T
+-----------+-----+---------------+
|+-+-+-----+|+---+|+---+-+-------+|
||4|&|count|||int|||3 8|&|inrange||
|+-+-+-----+|+---+|+---+-+-------+|
+-----------+-----+---------------+
And that exposition pretty much follows the thought process I
originally used to compose the sentence.
Thanks,
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