Compare Dates

Hi All,

Here is a good one: I need to compare 2 dates, without the year.
Basically I want to know if a specific calendar date falls between two
other dates. Everything is in YYYY-MO-DD, the way Perl wants it.

So, say I am looking for a birthday. I do not care about the year, I
just want to know if a birthday falls between two dates in the
calendar.......

Any suggestions? Date::Manip??? Did not seem to do what I want.

Thanks!

Re: Compare Dates

amerar@iwc.net wrote:
> Here is a good one: I need to compare 2 dates, without the year.
> Basically I want to know if a specific calendar date falls between two
> other dates. Everything is in YYYY-MO-DD, the way Perl wants it.

Just strip the year:

my $day = substr $date, 5;

and do stringwise comparisons.

--
Gunnar Hjalmarsson
Email: http://www.gunnar.cc/cgi-bin/contact.pl

Re: Compare Dates

amerar@iwc.net wrote:
> Hi All,
>
> Here is a good one: I need to compare 2 dates, without the year.
> Basically I want to know if a specific calendar date falls between two
> other dates. Everything is in YYYY-MO-DD, the way Perl wants it.
>
> So, say I am looking for a birthday. I do not care about the year, I
> just want to know if a birthday falls between two dates in the
> calendar.......
>
$birthdate = '1978-11-02';
$birthday = '11-02';

if(substr($birthdate,5) eq $birthday) {print "Bingo";}
--

Petr Vileta, Czech republic
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from another non-spammer site please.)

Re: Compare Dates

On Fri, 31 Aug 2007 09:24:36 -0700, amerar@iwc.net wrote:

> Here is a good one: I need to compare 2 dates, without the year.
> Basically I want to know if a specific calendar date falls between two
> other dates. Everything is in YYYY-MO-DD, the way Perl wants it.
>
> So, say I am looking for a birthday. I do not care about the year, I
> just want to know if a birthday falls between two dates in the
> calendar.......
>
> Any suggestions? Date::Manip??? Did not seem to do what I want.

Change the year of all your dates to be the same arbitrary year (make it a
leap year), then use the Day_of_Year function from
Date::Calc to get the day of the year (see
http://www.unix.org.ua/orelly/perl/cookbook/ch03_07.htm), then compare the
numbers.

Re: Compare Dates

Ben Bullock wrote:
>
> Change the year of all your dates to be the same arbitrary year (make it a
> leap year), then use the Day_of_Year function from
> Date::Calc to get the day of the year (see
> http://www.unix.org.ua/orelly/perl/cookbook/ch03_07.htm), then compare the
> numbers.

Or just use the month and day while assuming all months have 32 days.

sub date_index {
(my ($m, $d)) = $_[0] =~ /^\d{4}-(\d{2})-(\d{2})$/;
return ($m<<5) + $d;
}

then just compare the results from date_index calls.


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