Re: Optimizing perl code performance

Perl's core modules include 'Memoize', which attempts to make functions faster by "trading space for time."

http://perldoc.perl.org/Memoize.html

But I'd have to do trial-and-error to see what worked. (I'm wondering if a regExp would be faster than split)

     /.*,.*,.*,.*,.*,.*,.*,.*,(*),.*/  
       my $X = $1
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Then you wouldn't even need to call chomp. (And in general, I'm wondering if it would speed things up to combine the other instructions.)

    chomp( my($line)=$_ ) ;
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UPDATE: It occurred to me that the code re-declares every variable again on every pass through the loop. It seems like it might help to try

my ($X, $Y, $A, $B, $C, $D);
while(<DATAIN>)
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Re^2: Optimizing perl code performance by QM (Parson) on Aug 17, 2015 at 09:33 UTC
I'm wondering if a regExp would be faster than split. `split` takes a regex, so an optimized regex similar to the split could only be marginally better, and potentially much worse, especially for simple cases like this. Likewise `chomp` is very simple, and is probably zillions of times faster than IO. Profile, then fiddle. Lather, rinse, repeat. -QM -- Quantum Mechanics: The dreams stuff is made of	[reply] [d/l] [select]

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Re^2: Optimizing perl code performance
by QM (Parson) on Aug 17, 2015 at 09:33 UTC

I'm wondering if a regExp would be faster than split.

split

Likewise chomp is very simple, and is probably zillions of times faster than IO.

Profile, then fiddle. Lather, rinse, repeat.

-QM
--
Quantum Mechanics: The dreams stuff is made of

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