Difference Between 2 24 hours format times?

homer09001

how do i go about working the elapsed time in hours beteween two 24 hour times:

heres my general code

<?php
$to = $_POST['totime'];   ///// first 24 hour time
$land = $_POST['landtime'];   ///// Second 24 hour time
$ICAO = $_POST['LandICAO'];   ///// Landing Airport
$frame = $_POST['frame'];   ///// a/c Frame Number

$fnltime = "$land - $to";

echo $fnltime

?>

problem being i need to to still be able to work it out if the person set one time as say 1800 and the 2nd time as 0200

so if it passes midnight i still need it to be able to work the elapsed time out got me?

so:
1) how do i convert the 24 hour number to acctual times
2) how do i find out elapsed time in hours

obsidian

do you also have the dates somewhere? without the dates, you really have no way of calculating such a formula.

homer09001

ermm well no i guess im going to have to place text boxes in the form so the user can put date of $to and date of $land

homer09001

if i get them, to enter the day what format do i put it in DD:MM:YY?

obsidian

well, there are several ways to do date/time conversions, but typically, a DATETIME field would be in YYYY-MM-DD HH:MM:SS. once it's in that format, you can use any of several PHP or mySQL functions to help with your calculations.

homer09001

and how do i do teh coversion / calculations?

obsidian

homer09001 wrote:
and how do i do teh coversion / calculations?

well, i'll show you one method, but there are several out there. this just happens to be one of my favorites. if you have two datetimes, and you want to know how many hours between, i'd write up a function like this:

function getFlightTime($start, $end) {
  $start = strtotime($start);
  $end = strtotime($end);
  $diff = abs($start - $end); // make sure you have the absolute value, just in case
  $hour = 60 * 60; // seconds in an hour
  $x = ceil($diff / $hour); // use ceil() to force rounding up on anything above a whole number
  return $x;
}

$startTime = "2006-03-01 12:00:00"; // departure time/date
$endTime = "2006-03-02 08:00:00"; // arrival time
echo "This is a " . getFlightTime($startTime, $endTime) . " hour flight!";

hope this helps.

homer09001

ok i put that itno my script and i keep getting 0 hour flight?

homer09001

ahh got it i entered the date wrong

obsidian

homer09001 wrote:
ahh got it i entered the date wrong

excellent

homer09001

acctualy how do i get it to include minutes?

obsidian

homer09001 wrote:
acctualy how do i get it to include minutes?

you'd need to adjust your math in your function a bit:

function getFlightTime($start, $end) {
  $result = array();
  $start = strtotime($start);
  $end = strtotime($end);
  $diff = abs($start - $end); // make sure you have the absolute value, just in case
  $min = 60; // seconds in a minute
  $hour = $min * 60; // seconds in an hour
  $result['hours'] = floor($diff / $hour); // use floor() to force rounding down
  $diff = $diff % $hour;
  $result['mins'] = ceil($diff / $min);
  return $result;
}

// now, when you call the function, you'll get an array with hours and mins:
$startTime = "2006-03-01 12:00:00"; // departure time/date
$endTime = "2006-03-02 08:00:00"; // arrival time
$time = getFlightTime($startTime, $endTime);
echo "Flight lasts {$time['hours']} hours and {$time['mins']} minutes.";

homer09001

brilliant perfect just what i needed one last questions

how do i get the results to appear as 24 hours?

e.g. a flight of 1 hour and 5 minutes appear as: 01:05

obsidian

homer09001 wrote:
brilliant perfect just what i needed one last questions

how do i get the results to appear as 24 hours?

e.g. a flight of 1 hour and 5 minutes appear as: 01:05

just modify your returned values slightly and output:

$startTime = "2006-03-01 12:00:00"; // departure time/date
$endTime = "2006-03-02 08:00:00"; // arrival time
$time = getFlightTime($startTime, $endTime);
$output = sprintf("%02d:%02d", $time['hours'], $time['mins']);
echo $output;