day of year

philiotis has asked for the wisdom of the Perl Monks concerning the following question:

when I query unix for the day of year it gives me 330 when I do this prommatically using perl I get 329, is this because the first of jan is 0 or is there something else that's wrong? below is the code

#Returns the Zulu data type
#Parameters: Number of minutes time will be offset - 0 for now     
sub getBinary_Zulu 
{
my $offset = $_[0];    
my $msec = 0;
my $epoch_time = time();
my $offset_time = $epoch_time + ($offset * 60);

my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime($
+offset_time);
$year += 1900;
print "$msec,$sec,$min,$hour,$yday,$year \n";    #debugging only
return pack("I6", $msec,$sec,$min,$hour,$yday,$year);        
}#end getBinary_Zulu
[download]

Comment on day of year Download Code

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Re: day of year by fglock (Vicar) on Nov 26, 2002 at 17:04 UTC
Sure. $yday is in the range 0..364 or 365 If you want "zulu time" you could use gmtime instead of localtime, maybe?.	[reply]
Re: day of year by lemming (Priest) on Nov 26, 2002 at 17:07 UTC
date +%j on a Linux box gives you the day of year starting at 1, so 1..36[56] localtime() gives you day of year starting at 0, so 0..36[45]	[reply]
Re: day of year by davorg (Chancellor) on Nov 26, 2002 at 20:26 UTC
Here's a radical thought. Instead of just guessing, why not check the documentation for localtime. $yday is the day of the year, in the range 0..364 (or 0..365 in leap years.) Wasn't that simple? -- <http://www.dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply]
Re: day of year by pg (Canon) on Nov 26, 2002 at 17:08 UTC
And on UNIX, when you do `date +%j` [download] The returned day of year for Jan. 1st is 001.	[reply] [d/l]
Re: day of year by tadman (Prior) on Nov 26, 2002 at 18:07 UTC
If you can use the `date` command to do it, you can always use it internally: `use POSIX 'strftime'; print strftime("%j", localtime(time()));` [download] The `strftime()` function is able to process these percent-style variables. This may help with your remapping. Otherwise, you can always just add one.	[reply] [d/l] [select]