php comparing timestamps within an hour +/-

Question

I have a conditional written that compares two timestamps and I need it to execute if the time difference between the control variable and the compared variable is within 1 hour plus or minus of the compared.

it looks like this right now which is obviously only less than & equal to:

if( ($departure - $item['time']) <= 3600) ): 

would changing <= to <=> work?

Answer 1

This <=> operator will offer combined comparison in that it will :

Return 0 if values on either side are equal
Return 1 if value on the left is greater
Return -1 if the value on the right is greater

What you want to do instead is to compare the absolute value of $departure - $item['time']

if(abs($departure - $item['time']) <= 3600)): 

Answer 2

No, the <=> operator just returns a -1/0/1 when one side is smaller/equal/larger respectively, and it only works in PHP7.

It actually seems that in your case $departure - $item['time'] could go into negative values (if $item['time'] is larger than $departure ) and so your if statement will evaluate to true in cases when, say, $item['time'] is two, three or more hours in the future from $departure .

Wouldn't something like this work?

$diff = $departure - $item['time'];
if ($diff <= 3600 && $diff >= -3600)
{
    // do what you have to do
}

&& (AND) is a logical operator which means that both smaller statements must evaluate to true, in order for the complete statement to be true.