Beefy Boxes and Bandwidth Generously Provided by pair Networks
"be consistent"

Comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

Another small speed up can be achieved by replacing

my $leaps = int( ($y - 1970) / 4 + 0.5 ); (((($y-1970)*365 +$leaps+MONTHS->{$m}+($d-1))*24 +$H)*60 +$M)*60 + +$S;


(((int(($y-1970)*365.25-.5)+MONTHS->{$m}+$d)*24 +$H)*60 +$M)*60 +$S;

in my experiments between 5 to 10%. All other attempts using split and unpack are much slower. I found substr to be very fast:

sub str2epoch3 { (((int((substr($_[0],12,4)-1970)*365.25-.5)+ MONTHS->{substr($_[0],8,3)}+substr($_[0],5,2))*24 +substr($_[0],1 +7,2))*60 + substr($_[0],20,2))*60 +substr($_[0],23,2); }

about 60% faster than BrowserUk's code. I wonder whether there is something wrong...

Here is my full code:
use strict; use warnings; use Benchmark qw/cmpthese/; use constant MONTHS => { qw[ Jan 0 Feb 31 Mar 59 Apr 90 May 120 Jun 151 Jul 181 Aug 212 Sep 242 Oct 272 Nov 303 Dec 334 ] }; sub str2epoch { my( $d, $m, $y, $H, $M, $S ) = $_[0] =~ m[^.... (\d\d) (...) (\d\d\d\d) (\d\d):(\d\d):(\d\d)] or die "Bad format $_[0]"; my $leaps = int( ($y - 1970) / 4 + 0.5 ); (((($y-1970)*365 +$leaps+MONTHS->{$m}+($d-1))*24 +$H)*60 +$M)*60 + +$S; } sub str2epoch2 { my( $d, $m, $y, $H, $M, $S ) = $_[0] =~ m[^.... (\d\d) (...) (\d\d\d\d) (\d\d):(\d\d):(\d\d)] or die "Bad format $_[0]"; (((int(($y-1970)*365.25-.5)+MONTHS->{$m}+$d)*24 +$H)*60 +$M)*60 +$ +S; } sub str2epoch3 { (((int((substr($_[0],12,4)-1970)*365.25-.5)+ MONTHS->{substr($_[0],8,3)}+substr($_[0],5,2))*24 +substr($_[0] +,17,2))*60 + substr($_[0],20,2))*60 +substr($_[0],23,2); } my $str = 'Fri, 01 Mar 2013 01:21:14 +0000'; cmpthese( -3, {BrowserUK => sub { str2epoch ($str) }, BUK2 => sub { str2epoch2($str) }, substr => sub { str2epoch3($str) }, } ); </readmore>

In reply to Re^2: High-speed Date Formatting by hdb
in thread *SOLVED* High-speed Date Formatting by Endless

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and all is quiet...

    How do I use this? | Other CB clients
    Other Users?
    Others musing on the Monastery: (4)
    As of 2017-09-21 02:53 GMT
    Find Nodes?
      Voting Booth?
      During the recent solar eclipse, I:

      Results (241 votes). Check out past polls.