Regarding code such as :
repeat for each line j in myVar
if item 1 of j > 1 and item 2 of j > tMin and item 3 of j < tMax then
end if
end repeat
I remember a discussion several years ago on this very list mentioning
that in the "if" line, the engine would drop evaluation as soon as a false
is encountered (which I think is a feature common to many languages now).
Therefore carefully organizing the order of the items in each line of myVar
can also be a way to preserve the speed of "repeat for each" when complex
testing must be done.
I wonder how "filter" compares to this...
Besides, when very complex testing must be done on several items of each
line j,
I found that speed can be even more preserved by spliting each line into
an array and comparing each array cell to a refernce array...
Example :
put 1 into Tref1["a"]
put 1 into Tref1["b"]
put 1 into Tref2[4]
put 1 into Tref2[15]
put 1 into Tref2[26]
repeat for each line j in myVar
split j using tab
if Tref1[j[1]] is not empty and Tref2[j[2]] is not empty then
end if
end repeat
jbv
> "Filter" is a wonderful command that's almost always much faster than
> "repeat for each...", provided you're looking for data across a
> collection comprised of single-column rows.
>
> Once you get to multiple columns and you're searching just one of them,
> "repeat for each..." scales linearly quite nicely but the performance of
> "filter" degrades almost geometrically.
>
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