SKILL command: setof , exists

Thu Jul 28, 2011 8:29 am   

Hi,

I have a large data list containing lists of which I would want to
process.
I'm wondering which of the codes below is more efficient:

caar(setof(x LargeLongList cadr(x)=="metal" ))
caar(exists(x LargeLongList cadr(x)=="metal" ))

I'm not sure how to check the runtime with Virtuoso's Debugger.
Can anyone enlighten me?

Thanks,
I-FAB

Sat Jul 30, 2011 5:37 pm   

On Jul 28, 9:29 am, I-F AB <cop0...@gmail.com> wrote:

Hi there,

"exists" is definitively faster than "setof" .
"exists" stops when find first element that satisfy condition.
"setof" will scan all the list and returns all the elemets that
satisfy condition.

Best Regards,
Marcel

Wed Aug 03, 2011 2:30 am   

Ah yes, thanks. That makes perfect sense.
BTW, google seems to be very slow in updating threads here - has
anyone got a clue why?