RE: Bsearch for closest match

Below is my understanding (which could be wrong)
- %lookup uses sequential search if array is declared without
ASCEND/DESCEND
- %lookup use some type of binary search when ASCEND/DESCEND is
specified.

The problem is that SORTA can to sort dynamic array.  So, even with the
ASCEND/DESCEND keyword, I still not able to get the binary search
benefits of %lookup.

Again, all statements above might be wrong.

 

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Jon Paris
Sent: Tuesday, August 22, 2006 11:34 AM
To: rpg400-l@xxxxxxxxxxxx
Subject: RE: Bsearch for closest match

I always though that lookup does not work for dynamic array.  I'll

test it out again.

The old LOOKUP op-code was not viable because it wanted to search all of
the elements defined in the DIM.  %LOOKUP however allows you to specify
not just the starting point but also the end point for the search - so
it can be used.

I'm not certain - but I don't think %Lookup will do a binary search when
you use %LookupGE - in which case it will perform at the speed of the
old LOOKUP op-code (i.e. slowly)

Jon Paris
Partner400

www.Partner400.com 

--
This is the RPG programming on the AS400 / iSeries (RPG400-L) mailing
list To post a message email: RPG400-L@xxxxxxxxxxxx To subscribe,
unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives at
http://archive.midrange.com/rpg400-l.