PHP how many hours are in certain interval [duplicate] - php

Question

This question already has answers here:
How do I find the hour difference between two dates in PHP?
(10 answers)
Closed 5 years ago.
I have datetimes in the following format:
Start: 2017-07-16 20:00
End: 2017-07-16 23:30
Start: 2017-07-18 21:30
End: 2017-07-19 00:30
I need to tell from these intervals how many hours (in 0,5 increments) are spent between 18:00-22:00 and 22:00-06:00 in total for a month.
Thanks in advance for any hint.
The current code I have is this, but I'm not sure if it is covering all timeframe possibilities:
<?php
date_default_timezone_set("UTC");
$start = array(
"2017-07-16 21:30:00",
"2017-07-16 18:00:00"
);
$end = array(
"2017-07-17 00:30:00",
"2017-07-16 18:30:00"
);
$amount_low = 0;
$amount_high = 0;
for($i = 0; $i < sizeof($start); $i++) {
$start_time = date("H:i:s", strtotime($start[$i]));
$end_time = date("H:i:s", strtotime($end[$i]));
$start_date = date("Ymd", strtotime($start[$i]));
$end_date = date("Ymd", strtotime($end[$i]));
// getting chunk before 22:00 if
if(
(strtotime($start[$i]) >= strtotime($start_date . " 18:00") && strtotime($start[$i]) < strtotime($start_date . " 22:00"))
&&
$start_date < $end_date
) {
$interval_low = strtotime($start_date . " 22:00") - strtotime($start[$i]);
$amount_low += ceil($interval_low / 1800) / 2;
}
//amount_high
if(strtotime($start[$i]) > strtotime($start_date . " 22:00") && strtotime($start[$i]) < strtotime($start_date . " 06:00")) {
$interval_high = strtotime($end[$i]) - strtotime($start[$i]); //needs further things
$amount_high += ceil($interval_high / 1800) / 2;
} elseif (strtotime($start[$i]) < strtotime($start_date . " 22:00") && strtotime($end[$i]) > strtotime($start_date . " 22:00")) {
$interval_high = strtotime($end[$i]) - strtotime($start_date . " 22:00");
$amount_high += ceil($interval_high / 1800) / 2;
} else {
$interval_low = strtotime($end[$i]) - strtotime($start[$i]);
$amount_low += ceil($interval_low / 1800) / 2;
}
}
echo $amount_low;
echo "\n$amount_high";
?>

Answer 1

Would this work for you?
$start = strtotime('2017-07-16 20:00');
$end = strtotime('2017-07-16 23:30');
$interval = $end - $start;
$hours = floor($interval / 1800)/2;
echo($hours);
This will display the total hours (in 0,5 increments) between the two dates (rounding down, so if it's 55 minutes, it's 0,5 hours; replace 'floor' with 'ceil' for the opposite).

Answer 2

I believe a part of your solution is found here from Aillyn
You can convert them to timestamps and go from there:
$hourdiff = round((strtotime($time1) - strtotime($time2))/3600, 1);
Dividing by 3600 because there are 3600 seconds in one hour and using round()
to avoid having a lot of decimal places.
$hourdiff = round((strtotime($time1) - strtotime($time2))/3600, 1);
This will give you a rounded hour difference between the two times. You could do something similar, just apply it for each interval for which ever month and adjust your math. There's not really going to be a single PHP function you can call to solve this.