time difference

[Roger_Ramjet]

Order of precedence with the plus and minus signs, just needs bracketting. Sorry, I never actually do any arithmetic in php so I'm not up on how it works. Must be adding $open to $now and then subtracting that from midnight. Simple fix

 $now = strtotime(date("h:i:s"));
$open = strtotime(9:30);
$close = strtotime(12:30);

switch (TRUE) {
case ($now<$open):
   $diff = $open-$now;
   $hours = floor($diff / 3600);
   $minutes = floor(($diff % 3600) / 60);
   $state = 'Market Closed<br />' . $hours . 'hours ' . $minutes . 'minutes till the market opens again';
   break;
case ($now<$close):
   $diff = $close-$now;
   $hours = floor($diff / 3600);
   $minutes = floor(($diff % 3600) / 60);
   $state = 'Market Open<br />' . $hours . 'hours ' . $minutes . 'minutes till the market closes';
   break;
default:
   $diff = (86400 - $now) + $open;
   $hours = floor($diff / 3600);
   $minutes = floor(($diff % 3600) / 60);
   $state = 'Market Closed<br />' . $hours . 'hours ' . $minutes . 'minutes till the market opens again';
}

Now we are forcing it to evaluate the midnight minus now before adding the opening time.

[wrathyimp]

thanks for the fix;
but now i just remembered; that the market will also be closed on weekends.

Sorry roger, but i just skipped it since i was tring to concentrate on the market open and close timing. This will be real though for me, seem its very complex piece of code.

Thank you.

[Roger_Ramjet]

Well, it is pretty straight forward really, and easy enough to solve in a messy way. Doing it elegently and efficiently will need a lot of thought though. No time right now so bear with me.

[bpat1434]

Just a side note:
PHP follows the basic laws of mathematics in that with addition & subtraction( + - ), it follows in the order it is viewed from left to right. Same with multiplication and division( * / ). Now, if there is both multiplication and/or division with addition & subtraction in the equation, then it will multiply & divide first, and then add or subtract.

Just something to help you as you think your logic through. Usually it's always a good idea to define just what items will be evaluated first though....

[Roger_Ramjet]

Well that is what I expected for the expression: left to right, first subtract the current time from midnight, then add the opening time.
Not what was happening though, or so the man sez.
Now, I believe in being very explicit in my coding and would usually have written it with the brackets to force the issue, but it was late at night when I wrote that and I just got sloppy - no excuse, just sloppy.
Still it reinforces my normal coding style - which I arrived at years ago because of just this sort of thing.

[Roger_Ramjet]

I thk that this just about does it, though there may be some error in my arithmetic.
To check this script you can substitue test times for the $now var and day of week rather than waiting for the earth to spin around.

$now = strtotime(date("H:i"));
$open = strtotime(9:30);

// set up midnight and closing time according to the day of the week
switch (date(w)) {
   case 1:
   case 2:
   case 3:
   case 4:
   // if it is mon, tues, wed, or thurs, closing time and midnight are normal
      $close = strtotime(12:30);
      $midnight = 86400;
      break;
   // friday, add 48 hours to midnight and closing time is normal
   case 5:
      $close = strtotime(12:30);
      $midnight = 345600;
      break;
   // sat add 24 hours to midnight and closing time is zero
   case 6:
      $close = 0;
      $midnight = 172600;
      break;
   // sunday midnight is normal and closing time is zero
   case 0:
      $close = 0;
      $midnight = 86400;
}

switch (TRUE) {
   // if it is after the market closed calculate time till next open
   // setting close to zero for sat and sun covers the weekend
   // adding extra days to midnight covers friday and saturday
   case ($now > $close):
      $diff = ($midnight - $now) + $open;
      $hours = floor($diff / 3600);
      $minutes = floor(($diff % 3600) / 60);
      $state = 'Market Closed<br />' . $hours . 'hours ' . $minutes . 'minutes till the market opens again';
      break;
   // if it is before opening time then calculate time till open
   case ($now < $open):
      $diff = $open-$now;
      $hours = floor($diff / 3600);
      $minutes = floor(($diff % 3600) / 60);
      $state = 'Market Closed<br />' . $hours . 'hours ' . $minutes . 'minutes till the market opens again';
      break;
   // otherwise the market is open
   default:
      $diff = $close-$now;
      $hours = floor($diff / 3600);
      $minutes = floor(($diff % 3600) / 60);
      $state = 'Market Open<br />' . $hours . 'hours ' . $minutes . 'minutes till the market closes';
} 

[wrathyimp]

Thanx again Roger, seems its working.

thanx alot..

let me wait till this week end to check if its woking.

[bpat1434]

Found a boo boo:

case 1:
case 2:
case 3:
case 4:
// Whatever code

case 5:
// friday

case 5:
// saturday

How can friday and saturday have the same day number? Saturday should be day 6 (and thus case 6) not case 5....

I'm not sure about your math, but PHP math works fine for me:
http://phpbuilder.bpatterson.net/userhelp/RogerRamjet/math.php

[wrathyimp]

Thanks all,

Special Thanks to ROGER, its working fine.

thankx once again.

[Roger_Ramjet]

So I got a typo, bpat, so what, I always have typos - I'm dixlexick.

[bpat1434]

Was just saying... he might not have caught it, and wondered why it doesn't work exactly perfectly. Whatever....

[wrathyimp]

Sorry to come back so late;

there is a problem on friday, that is show market will open on the next day, i.e. it gives the hrs & minutes to calculate till the next day; before the market is open.

It works fine after market close i.e. 12:30

I think its will the midnight settings. Can we just say like
if day = sat & sun (market closed for weekend). without calcutaing the midnight or all the week days.

Need help.

[Roger_Ramjet]

You could certainly do that for Fri, Sat and Sun.

I am surprised that Fri is miscalculating. It should work, setting the closing time to 12:30 for all weekdays should mean that it fails the first case: not after closing-time; and is true in the second case, before opening-time. The vars for now and open never change for any day of the week so if the calculation works for one day it should work for all days. (Sat and Sun never get that far because the market is always closed and the are dealt with by the first case.)> Finally if it is not after close and not before open then the market is open by default and again the same calculation is used for all weekdays so if it works for one it should work for all.