mktime not calculating correctly?

access9

This is driving me crazy!

Goal: To find out the number of days from when a contract is signed to when it expires.

Problem: Although I can generate time stamps for both the expiration date and signage date, it almost always comes out to 1096 days difference, regardless of the date.

I pull out the date a contract was signed from the DB, for example, 2003-09-22. I increment the year based on the type of contract (Three year for example). So the expiration date would be 2006-09-22.

Here is my code:

/* Get contract date by month, day and year */
list($contract_year, $contract_month, $contract_day) = explode('-', $customer['date_signed']);

/* Get contract_timestamp */
$contract_timestamp = mktime(0, 0, 0, $contract_month, $contract_day, $contract_year, 0);

/* Three year contracts */
if ($customer['contract_type'] == 'Three Year') {

/* Increment year by 3 */
$expiration_year = ($contract_year + 3);

/* Assign logical variable names */
$expiration_month = $contract_month;
$expiration_day   = $contract_day;
}

/* Get expiration timestamp */
$expiration_timestamp = mktime(0, 0, 0, $expiration_month, $expiration_day, $expiration_year, 0);

/* Find out the days to expiration */
$days_left = ($expiration_timestamp - $contract_timestamp) / 86400;

I thought maybe I needed to (int) my vars first, but that didn't make a difference. Does anyone have an idea why this is happening?

Thanks,
a9

tbach2

are you sure that $customer['date_signed'] is really what you think it is? Try debugging with

print "<pre>"; print_r($customer); print "</pre>";

I'm betting that it doesn't have a value assigned 😉

access9

I wish it were that simple. Here's my sample output from the above suggestion:
Array
(
[0] => 260
[ID] => 260
[1] => Three Year
[contract_type] => Three Year
[2] => 2000-9-30
[date_signed] => 2000-9-30
)

tbach2

Your array doesn't look right... It could be that your data structure is killing you. How did you assign the variable? I would suggest something like

// however you get your values...
$id= 260;
$type = 'Three Year';
$date_signed = '2000-9-3';

// note I'm assigning an array to an 'auto-incrementing' array
$customer[] = array('ID'=>$id,
                    'contract_type'=>$type,
                    'date_signed'=>$date_signed
                    );

keith73

there are 1095 days in a 3-year span, add 1 more because 2004 is a leap year.

Have you tried changing the plan from 3 years to another length to see what that gets you?

I don't see where there is a problem.

The calculation is correct and no matter what you enter for the starting date, if the plan is 3 years, you will always get that #.

PS - your print_r output of the array leads me to believe that you're using mysql_fetch_array. Personally, I use mysql_fetch_assoc when I want array results. mysql_fetch_array is just taking up memory with redundant data, unless you have a need for the numbered indices.

keith

ahundiak

I think the problem is that there is not exactly 365 days to a year (I assume you think the correct answer is 1095). It's the leap year that gives you an extra day.

Looks like Kieth73 beat me to the answer. I guess I type slow.

access9

Keith is right, I was using mysql_fetch_array (never learned to use otherwise), thanks for the tip!

Here is the data assigned to my variables:
$contract_month = 09;
$contract_day = 30;
$contract_year = 2000;
$contract_timestamp = mktime(0, 0, 0, $contract_month, $contract_day, $contract_year, 1);

$expiration_month = 09;
$expiration_day = 30;
$expiration_year = 2003;
$expiration_timestamp = mktime(0, 0, 0, $expiration_month, $expiration_day, $expiration_year, 1);

Here is an example output:
Contract Timestamp: 970290000
Expiration Timestamp: 1064898000

$days_left = ($expiration_timestamp - $contract_timestamp) / 86400;

$days_left is 1095. What the heck? Given my ample above, it should be 8! If it's a leap year, so a day gets added (which I'll figure out later), but it should not be 1095.

access9

How about this: I'm losing my freaking mind! I'm trying to caculate the number of days left on the contract (in relation to today's date), but my code is calculating the number of days between when the contract was signed and the date it expires.

Grrr, I was looking too hard in my code for errors, but didn't see the flaw in my logic.

keith73

We've all been there before. That's why these forums are a big help, post your problem and someone will see the solution.

keith