which formula do i use?

[matthew9090]

ive got this so far

 

$difference = strtotime($time_current) - strtotime($time_old);
$formula = $production_per_hour / $difference + $current_number;
$round = round($formula, 0);

 

so i need to calculate from a timestamp in the database what the new number will be. i just don't know what to divide, times, plus or minus. ive fiddled around with it to see if i could get it right.

[btherl]

What formula are you trying to implement?

[matthew9090]

this one

 

 formula = $production_per_hour / $difference + $current_number; 

 

it needs to calculate the new value from a timestamp using the difference

 

$difference = strtotime($time_current) - strtotime($time_old);

 

the production per hour and the current value

 

 

[btherl]

I still don't understand - you have given me a formula in PHP, and you are asking me if it is correct.  How can I tell you if it is correct unless you tell me what you are trying to calculate?

[matthew9090]

im trying to calculate the new value from a timestamp. there is the

 

current production per hour

the current value

the time difference from now to the last updated timestamp

 

so depending on the production per hour the number will go up every so often

[matthew9090]

so if the production per hour is 60 then that is 1 per minute. so it needs to go up by 1 per minute. and if the production per hour is 120 then that is 2 every minute. i just nned the right formula to work  it out.

[ignace]

What is the value of $time_current, $time_old and $current_number?

 

var_dump($time_current, $time_old, $current_number);

 

Run this and tell us the output.

[matthew9090]

it outputs this:

 

string '2011-04-12 09:25:26' (length=19)

string '2011-04-12 09:25:16' (length=19)

string '0' (length=1)

[sasa]

$formula = $production_per_hour / 3600 * $difference + $current_number;