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Re^4: a close prime number

by dragonchild (Archbishop)
on Feb 14, 2005 at 19:11 UTC ( #430894=note: print w/ replies, xml ) Need Help??


in reply to Re^3: a close prime number
in thread a close prime number

It's not. 

use Benchmark qw( cmpthese );

my $large_number = 3 * 1234647389;

cmpthese( -1, {
    modulo => sub { $large_number % 3 == 0 },
    divide => sub { my $v; $v += $_ for split //, $large_number; $v % 
+3 == 0},
});

--------

            Rate divide modulo
divide   30919/s     --   -99%
modulo 2120579/s  6759%     --

[download]

By a factor of 67 times faster. Or so ...

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Comment on Re^4: a close prime number
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Re^5: a close prime number
by RazorbladeBidet (Friar) on Feb 14, 2005 at 19:15 UTC
    Darn - so !(faster in my head == faster in code) :)

    Thanks for the benchmarks, dragonchild.
[reply]

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