Julian Date to Calender date conversion. Please help!

[charanya]

I am new to Perl, I am trying to convert Julian date to calendar date (day of the year). For example, 26711 corresponds to 24-Sep-2011. I tried two approach to this, none being successful.

1) I saw this code online, but this code returns wrong date. This code does not return 24-Sep-2011, instead returns 26-Sep-2011 (Which is wrong!)

date_from_yday()
{
perl -e '
use Time::Local;

$yr = $ARGV[0] - 1900;
$yday = $ARGV[1];
$mytime = timelocal(1,0,0,1,1,$yr);
$mytime += ( 86400 * $yday );
($sec,$min,$hour,$day,$mon,$yr,$wday,$yday,$whocares) =
localtime($mytime);
$yr += 1900;
printf("%02d/%02d/%d\n", $day, $mon, $yr);

' $2 $1
}

date_from_yday 267 2011

-----------

2) I tried connecting to oracle db and fetch the date.

$RETVAL=`"select to_date(nvl(SUBSTR(126711 , 2 , 5) , '00179'), 'DDDYY') from dual" | $ORACLE_HOME/bin/sqlplus -L -S $CONNECT_STRING`;

This gives me error saying "select to_date(nvl(SUBSTR(126711 , 2 , 5) , '00179'), 'DDDYY') from dual : not found". I know the connection string is correct because that is used by other queries in the script.

Any help is appreciated. If there is a new approach to it, i can try that too. Please help ASAP.

Thanks

Charanya

 

[MillerH]

The following will get you part of the way there. You'll still have to do the parsing and potentially install the DateTime module on your system:

use DateTime;

use strict;
use warnings;

my $dt = DateTime->new(
	year	=> 2011,
	month	=> 1,
	day 	=> 1,
);

$dt->add(days => 266);


print $dt->strftime("%b %d, %Y");

# Prints Sep 24, 2011

- Miller