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Re: Null-stripping performance

by BrowserUk (Pope)
on Feb 26, 2007 at 13:13 UTC ( #602115=note: print w/replies, xml ) Need Help??

in reply to Null-stripping performance

You'd almost certainly be faster to unpack the entire string into an array once and then just index into the array:

my @numbers = unpack '(a4)*', $string;; ## Requires 5.8.x sub fetchOne { my $index = shift; return $numbers[ $index ]; }

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Re^2: Null-stripping performance
by qiau (Initiate) on Feb 26, 2007 at 13:52 UTC
    Oh, forgot to say that the strings are pretty large so I don't think arrays would be the best solution.

    Each string is about 1 Mbyte that I read in from a file upon request so a standard use is to open about four files (sometimes more, sometimes less) and read values from different indexes in those strings.

    I think I tried with a array in the beginning but realized that splitting into 1 Mbyte arrays wasn't fast at all :).

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