calculating time using timestamps

[Anon]

Hello,

I wonder if you can help please?

I have two UNIX timestamps:

1. 2001-09-05 14:40:55
2. 2001-10-06 14:40:55

I need to calculste the number of days between these 2 timestamps. Does anyone know how to do this please?

I've tried:

$number_of_days = (2001-09-05 14:40:55 - 2001-10-06 14:40:55);

...but this doesn't do it.

Thank you if you can help.

Regards,

Jason

[Anon]

Is that actually a line of code you tried? Anyway, if the two dates are in two variables then you can do the following.

$d1 = '2001-09-05 14:40:55';
$d2 = '2001-10-06 14:40:55';

function ParseDate($date) {
preg_match("/^{([0-9]{4})-([0-9]{2})-([0-9]{2})/",} $date, $array);
array_shift($array);
return $array;
}

list ($y1, $m1, $d1) = ParseDate($d1);
list ($y2, $m2, $d2) = ParseDate($d2);
$time_diff = mktime(0, 0, 0, $m1, $d1, $y1) - mktime(0, 0, 0, $m2, $d2, $y2);
$days_elapsed = $time_diff/60/60/24;
if ($days_elapsed < 0 ? $mult = -1 : $mult = 1)
print $days_elapsed*$mult;

[blackmamba]

Ouch! That looks way too long winded to me 😃
This would probably be more efficient:

Before I start, these to dates are not timestamps (timestamps are the number of seconds since Jan 1970), they are simply datetime strings.
2001-09-05 14:40:55
2001-10-06 14:40:55
Using strtotime ( ) will give you a timestamp back for each datetime i.e.

$dif = strtotime ( "2001-10-06 14:40:55" ) - strtotime ( "2001-09-05 14:40:55" );

Now you'll have the difference in seconds between the 2 dates. To get the difference in days do the following:

$dif = $dif / 60 / 60 / 24;

You might get some decimal places in some cases, so it might make sense to use a rounding function i.e.

$dif = floor ( $dif / 60 / 60 / 24 );

That will give you the number of whole days, losing any extra hours on the end.

[Anon]

Thanks a million for this code i was breaking my head for the past 20 hours to get a solution but my requirement was to find the difference betweeb 2 dates in hours.I slightly modified ur end code and it satisfied my requirement
Thanks
Saravanan

Donncha Fahy wrote:

Ouch! That looks way too long winded to me 😃
This would probably be more efficient:

Before I start, these to dates are not timestamps (timestamps are the number of seconds since Jan 1970), they are simply datetime strings.
2001-09-05 14:40:55
2001-10-06 14:40:55
Using strtotime ( ) will give you a timestamp back for each datetime i.e.

$dif = strtotime ( "2001-10-06 14:40:55" ) - strtotime ( "2001-09-05 14:40:55" );

Now you'll have the difference in seconds between the 2 dates. To get the difference in days do the following:

$dif = $dif / 60 / 60 / 24;

You might get some decimal places in some cases, so it might make sense to use a rounding function i.e.

$dif = floor ( $dif / 60 / 60 / 24 );

That will give you the number of whole days, losing any extra hours on the end.