Add fractional hours to a DateTime in php - php

Question

I have a system which I need to add a certain amount of fractional hours.
I've been searching and this is what I got, by far it's the most accurate method, but still doesn't give me the answer I need
function calculateHours($hours){
$now = new DateTime("2017-10-25 10:23:00");
$time = array();
$time = explode(".", $hours);
$time [1] += $time [0]*60;
$now->modify("+".$time[1]." hours");
return $now;
}
$diff = 119.23;
$answer = calculateHours($diff);
echo $answer ->format('Y-m-d H:i:s');
The answer that I want to reach is "2017-11-09 11:00:00" and I receive "2017-10-25 12:22:23" instead

Answer 1

Adding the hours is not correct. When you multiply hours times 60 it will make minutes.
This code should work.
function calculateHours($hours){
$now = new DateTime("2017-10-25 10:23:00");
$time = explode(".", $hours);
$time[1] += $time[0]*60;
$now->modify("+".$time[1]." minutes");
return $now;
}
$diff = 119.23;
$answer = calculateHours($diff);
echo $answer->format('Y-m-d H:i:s');
Result is 2017-10-30 09:46:00

Answer 2

You should use DateInterval php class to create an inverval with x seconds from your $hours variable.
Then you just have to use the datetime add interval method to modify your date
Please take a look a this example
function calculateHours($hours){
$now = new DateTime("2017-10-25 10:23:00");
var_dump($now);
$timeParts = explode(".", $hours);
// Where 23 is a percentage of on hour
$minutes = $timeParts[0] * 60 + round($time[1] * 60 / 100);
// Where 23 is the number of minutes
$minutes = $timeParts[0] * 60 + $time[1];
$interval = new DateInterval(sprintf('PT%dM', $minutes));
$now->add($interval);
echo $now->format('Y-m-d H:i:s');
return $now;
}

Answer 3

Use date_add
date_add($now, date_interval_create_from_date_string($tempo[1]' hours'));
or as object:
$now->add( DateInterval::createFromDateString($tempo[1].' hours'));