Correct way to make a schedule - php

Question

I've been debating whether to use Date functions or just whether there is a cleaner way to make an array of a given day's minutes at the moment my code reads like this;
function emptySchedule()
{
$emptySchedule = [];
for ($h = 0; $h < 24; ++$h) {
for ($m = 0; $m < 60; ++$m) {
$emptySchedule[str_pad($h, 2, '0', STR_PAD_LEFT).':'.str_pad($m, 2, '0', STR_PAD_LEFT)] = [];
}
}
return $emptySchedule;
}
But it just feels dirty, is there a better way to achieve the same result or maybe a better way to handle the minutes in the day with a date object or even better a globally accepted correct way? I'd prefer not to use a package, but if there is a good one I'm open to it.
EDIT; for some context, I will be putting arrays into each minute of the day.
EDIT2: for the purpose of what this will be used for there is no need for any input, my final function was;
public function emptySchedule()
{
$startDate = date_create("today"); //Any start date works
$endDate = date_create("tomorrow"); //Any end date works
$step = new \DateInterval("PT1M"); //1 minute, can change
$date = $startDate;
$times = [];
while ($date <= $endDate) {
$times[$date->format("H:i")] = [];
$date = $date->add($step);
}
return $times;
}

Answer 1

This is what I'd do:
$startDate = date_create("today"); //Any start date works
$endDate = date_create("tomorrow"); //Any end date works
$step = new DateInterval("PT1M"); //1 minute, can change
$date = $startDate;
$times = [];
while ($date <= $endDate) {
$times[$date->format("H:i")] = [];
$date = $date->add($step);
}
print_r($times);
http://sandbox.onlinephpfunctions.com/code/dd91a8f3f1707ca20aae93f70969275d5fb8dedd

Answer 2

Well, a more elegant approach of your code is:
<?php
function emptySchedule($hoursInit = date('G'), $hoursActive = 24)
{
$emptySchedule = [];
for ($h = $hoursInit; $h < $hoursActive; ++$h) {
for ($m = 0; $m < 60; ++$m) {
$emptySchedule[sprintf('%02d:%02d', $h, $m)] = [];
}
}
return $emptySchedule;
}
You can use interval too, working with lunch hours in your schedule and stuff:
<?php
function emptySchedule($hoursInit = date('G'), $hoursActive = 24, $interval = false)
{
$emptySchedule = [];
for ($h = $hoursInit; $h < $hoursActive; ++$h) {
if ($interval && ($h < $interval['start'] || $h > $interval['end'])) {
for ($m = 0; $m < 60; ++$m) {
$emptySchedule[sprintf('%02d:%02d', $h, $m)] = [];
}
}
}
return $emptySchedule;
}
But, like #deceze said, using date functions is a must, it's not simple to do right now, I'll try to figure out a better way;