From: mose@ns.ccsn.edu (Russell Mosemann)
Subject: Re: Friday 13th, try it yourself (was Language Wars..)
Date: 1996/09/21
Date: 1996-09-21T00:00:00+00:00 [thread overview]
Message-ID: <521pfp$kec@ns.ccsn.edu> (raw)
In-Reply-To: 3242D1EB.3F54@ford.com
Clinton Pierce <cpierce1@ford.com> writes:
>See for yourself if the "Friday the 13th" thing is just a UL. If you trust
>UNIX's 'cal' program, and that it does the Right Thing with Leap Years, the
>Gregorian/Julian switch etc..etc... This Perl script will show you the Truth:
I decided to write a script of my own for Solaris 2.4 and perl
5.003 which calls cal for 1066 to 1996 and rips out the Fridays. The
following is the number of times a particular day of the month falls
on a Friday. The results are pretty evenly distributed, i.e. it is an
Urban Legend.
Day of month: 1 Freq: 1600
Day of month: 2 Freq: 1594
Day of month: 3 Freq: 1596
Day of month: 4 Freq: 1594
Day of month: 5 Freq: 1593
Day of month: 6 Freq: 1601
Day of month: 7 Freq: 1593
Day of month: 8 Freq: 1600
Day of month: 9 Freq: 1594
Day of month: 10 Freq: 1596
Day of month: 11 Freq: 1594
Day of month: 12 Freq: 1593
Day of month: 13 Freq: 1601
Day of month: 14 Freq: 1593
Day of month: 15 Freq: 1601
Day of month: 16 Freq: 1594
Day of month: 17 Freq: 1596
Day of month: 18 Freq: 1594
Day of month: 19 Freq: 1593
Day of month: 20 Freq: 1601
Day of month: 21 Freq: 1593
Day of month: 22 Freq: 1601
Day of month: 23 Freq: 1594
Day of month: 24 Freq: 1596
Day of month: 25 Freq: 1594
Day of month: 26 Freq: 1593
Day of month: 27 Freq: 1601
Day of month: 28 Freq: 1593
Day of month: 29 Freq: 1499
Day of month: 30 Freq: 1461
Day of month: 31 Freq: 930
The script is
#!/usr/bin/perl
@dom = ();
for ($year = 1066; $year <= 1996; $year++)
{
open(CAL, "cal $year |");
$row = <CAL>; # Get rid of year
$row = <CAL>; # A blank line
while($row = <CAL>)
{
for ($cols = 0; $cols < 3; $cols++)
{
$day = substr($row, 15 + ($cols * 23), 2);
$dom[$day]++ if $day =~ m/^( |\d)\d$/;
}
}
close(CAL);
}
for ($day = 1; $day <= 31; $day++)
{
print "Day of month: $day Freq: $dom[$day]\n";
}
--
Russell Mosemann Concordia College Voice: (402) 643-7445
Computing Center Seward, NE 68434 Fax: (402) 643-4073
"If Teflon is non-stick, how do they get it to stick to the pan?"
next prev parent reply other threads:[~1996-09-21 0:00 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
1996-09-13 0:00 language wars (results 13 September) last posting Roy Gardiner
1996-09-13 0:00 ` William Clodius
1996-09-13 0:00 ` Peter Seebach
1996-09-21 0:00 ` Robert Dewar
1996-09-21 0:00 ` Robert Dewar
1996-09-16 0:00 ` Robert Fahey
1996-09-18 0:00 ` James Giles
1996-09-18 0:00 ` Andrew Gierth
1996-09-18 0:00 ` Luke Chao
1996-09-18 0:00 ` Norman H. Cohen
1996-09-18 0:00 ` James Giles
1996-09-19 0:00 ` Andrew Gierth
1996-09-19 0:00 ` Daniel J. Long
1996-09-21 0:00 ` Ken Pizzini
1996-09-24 0:00 ` Art Schwarz
1996-09-26 0:00 ` Matthew D. Healy
1996-09-29 0:00 ` Randy MacDonald
1996-10-03 0:00 ` galina.kasminskaya
1996-10-03 0:00 ` Dave Tholen
1996-09-26 0:00 ` Ken Pizzini
1996-09-29 0:00 ` Paul Gilmartin
1996-09-21 0:00 ` Ken Pizzini
1996-09-19 0:00 ` Norman H. Cohen
1996-09-20 0:00 ` John Girash
1996-09-20 0:00 ` John Girash
1996-09-20 0:00 ` Friday 13th, try it yourself (was Language Wars..) Clinton Pierce
1996-09-21 0:00 ` Russell Mosemann [this message]
1996-09-21 0:00 ` Russell Mosemann
1996-09-25 0:00 ` Barrie Walker
1996-09-26 0:00 ` Jim Shapiro
1996-09-25 0:00 ` Ken Pizzini
1996-09-25 0:00 ` Results of my test: Re: Friday 13th, try it yourself Lee Crites
1996-09-25 0:00 ` William Clodius
1996-09-27 0:00 ` Dik T. Winter
[not found] ` <52qpqt$1b3l@ilx018.iil.intel.com>
1996-10-02 0:00 ` Ken Pizzini
1996-10-02 0:00 ` Dik T. Winter
1996-09-26 0:00 ` Dr John Stockton
1996-09-26 0:00 ` Lee Crites
1996-09-26 0:00 ` Daan Sandee
1996-09-26 0:00 ` Jeff Drummond
1996-09-30 0:00 ` Ray Dunn
1996-09-26 0:00 ` John Winters
1996-09-26 0:00 ` Adam Beneschan
1996-09-27 0:00 ` Glen Clark
1996-09-27 0:00 ` CHI Research, Inc.
1996-09-27 0:00 ` Lee Crites
1996-09-28 0:00 ` John Winters
1996-09-30 0:00 ` Adam Beneschan
1996-10-01 0:00 ` Mike McCarty
1996-09-26 0:00 ` Dr John Stockton
[not found] ` <199609302101.JAA04610@kauri.vuw.ac.nz>
1996-09-30 0:00 ` Lee Crites
1996-09-23 0:00 ` Friday 13th, try it yourself (was Language Wars..) Matthew D. Healy
1996-09-23 0:00 ` Dik T. Winter
1996-09-25 0:00 ` Paul Gilmartin
1996-09-22 0:00 ` Dr John Stockton
1996-09-23 0:00 ` Dr John Stockton
1996-09-23 0:00 ` Randy MacDonald
1996-09-23 0:00 ` Dik T. Winter
1996-09-25 0:00 ` John Harper
1996-09-25 0:00 ` jupiter
1996-09-24 0:00 ` language wars (results 13 September) last posting Andrew Gierth
1996-09-24 0:00 ` Art Schwarz
-- strict thread matches above, loose matches on Subject: below --
1996-09-25 0:00 Friday 13th, try it yourself (was Language Wars..) Barrie Walker
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