Re: [Boston.pm] a question

Were you surprised by Daylight Savings Time?

On Sun, Jan 29, 2017 at 11:32 AM dan moylan <[email protected]> wrote:

>
>
> in fiddling with a perl script to calculate the variable
>
> dates dependent on the date of easter, using Time::Local, i
>
> got the wrong answers for shrove tuesday 47 and ash
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> wednesday 46 days before easter.  this turned out to be what
>
> appears to me as an anomoly in Time::Local at 20170313 where
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> the delta seconds between days was 3600 sec short.  a test
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> script then found a corresponding anomoly at 20171106 where
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> the delta seconds was 3600 sec long.  fwiw i attach the test
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> script.  have i missed something obvious?
>
>
>
> #! /usr/bin/perl
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> # tsttme.pl
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> # created 170129 by jdm3
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> # revised 170129 by jdm3
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>
>
>   use strict;
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>   use Time::Local;
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>
>
>   my ($dlt, $dte, $tme, $tmepre, $mth, $Mth, $day, $year, );
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>   my (@dim, @mth, );
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>
>
>   $year = $ARGV[0];
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>   if (! $year) {
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>       printf ("enter the year, stupid.\n");
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>       exit (0);
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>   }
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>
>
>   @dim = qw (31 28 31 30 31 30 31 31 30 31 30 31);
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>   @mth = (0 .. 11);
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>
>
>   if ($year%4 == 0) { $dim[1] = 29; }
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> # printf ("feb: $dim[1]\n");
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>
>
>   $tmepre = &Time::Local::timelocal (0,0,0,31,11,$year-1901);
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>   foreach $mth (@mth) {
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>       foreach $day (1..$dim[$mth]) {
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>           $tme = &Time::Local::timelocal (0,0,0,$day,$mth,$year-1900);
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>           $dlt = $tme - $tmepre;
>
>         # printf ("$year$mth$day -- $dlt\n");
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>           $day = sprintf ("%02d", $day);
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>           $Mth = sprintf ("%02d", $mth+1);
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>           if ($dlt != 86400) { printf ("$year$Mth$day -- $dlt\n"); }
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>           $tmepre = $tme;
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>       }
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>   }
>
>
>
> ##########################################################################
>
>
>
> tia,
>
> ole dan
>
>
>
>
>
> j. daniel moylan
>
> 84 harvard ave
>
> brookline, ma 02446-6202
>
> 617-777-0207 (cel)
>
> [email protected]
>
> www.moylan.us
>
> [no html pls]
>
>
>
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