You need to find the number of days between two dates or times.
If your dates are in Epoch seconds, and fall in the range
2038 (inclusive), simply subtract one from the other and convert the seconds to days.
$seconds = $recent - $earlier;
use Date::Calc qw(Delta_Days); $days = Delta_Days( $year1, $month1, $day1, $year2, $month2, $day2);
It also calculates the difference between dates and times:
use Date::Calc qw(Delta_DHMS); ($days, $hours, $minutes, $seconds) = Delta_DHMS( $year1, $month1, $day1, $hour1, $minute1, $seconds1, # earlier $year2, $month2, $day2, $hour2, $minute2, $seconds2); # later
One problem with Epoch seconds is how to convert the large integers back to forms that people can read. The following example shows one way of converting an Epoch seconds value back to its component numbers of weeks, days, hours, minutes, and seconds:
$bree = 361535725; # 16 Jun 1981, 4:35:25 $nat = 96201950; # 18 Jan 1973, 3:45:50 $difference = $bree - $nat; print "There were $difference seconds between Nat and Bree\n";
$seconds = $difference % 60; $difference = ($difference - $seconds) / 60; $minutes = $difference % 60; $difference = ($difference - $minutes) / 60; $hours = $difference % 24; $difference = ($difference - $hours) / 24; $days = $difference % 7; $weeks = ($difference - $days) / 7; print "($weeks weeks, $days days, $hours:$minutes:$seconds)\n";
There were 265333775 seconds between Nat and Bree
(438 weeks, 4 days, 23:49:35)
Date::Calc's functions can ease these calculations.
Delta_Days function returns the number of days between two dates. It takes the two dates as a list: year, month, day. The dates are given chronologically - earliest first.
use Date::Calc qw(Delta_Days); @bree = (1981, 6, 16); # 16 Jun 1981 @nat = (1973, 1, 18); # 18 Jan 1973 $difference = Delta_Days(@nat, @bree); print "There were $difference days between Nat and Bree\n";
There were 3071 days between Nat and Bree
use Date::Calc qw(Delta_DHMS); @bree = (1981, 6, 16, 4, 35, 25); # 16 Jun 1981, 4:35:25 @nat = (1973, 1, 18, 3, 45, 50); # 18 Jan 1973, 3:45:50 @diff = Delta_DHMS(@nat, @bree); print "Bree came $diff days, $diff:$diff:$diff after Nat\n";
Bree came 3071 days, 0:49:35 after Nat