in reply to Re: grep for lines containg two variables
in thread grep for lines containg two variables
seems that lookahead grep is the slightly faster solution ...
here is the test script I used:
... and the results#!/usr/bin/perl -w # usage : ./this_script.pl < input_file > captured_benchmarks use strict; use Benchmark; my @data=<>; my (@res1,@res2,@res3); timethese (100000000, { grep_and => q{ @res1 = grep /GGGGGACACCTTCTCTCTCT/ && /RH_MEa0001bG06/, @data; }, double_grep => q{ @res2 = grep /GGGGGACACCTTCTCTCTCT/,grep /RH_MEa0001bG06/,@data; }, lookahead_grep => q{ @res3 = grep /^(?=.*GGGGGACACCTTCTCTCTCT)(?=.*RH_MEa0001bG06)/,@da +ta; } } );
Benchmark: timing 100000000 iterations of double_grep, grep_and, looka +head_grep... double_grep : 27 wallclock secs (26.98 usr + 0.00 sys = 26.98 CPU) @ 3705899.79/s ( +n=100000000) grep_and : 24 wallclock secs (23.05 usr + 0.00 sys = 23.05 CPU) @ 4338959.52/s ( +n=100000000) lookahead_grep : 24 wallclock secs (22.83 usr + 0.00 sys = 22.83 CPU) @ 4380585.25/s ( +n=100000000)
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Re^3: grep for lines containg two variables
by ikegami (Patriarch) on Dec 08, 2005 at 01:09 UTC | |
by l3v3l (Monk) on Dec 08, 2005 at 17:54 UTC | |
by ikegami (Patriarch) on Dec 08, 2005 at 18:35 UTC | |
by l3v3l (Monk) on Dec 08, 2005 at 19:55 UTC |
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