Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw
 
PerlMonks  

Re^4: efficient determination of in/out of hours

by Random_Walk (Prior)
on Oct 18, 2013 at 05:57 UTC ( [id://1058708]=note: print w/replies, xml ) Need Help??


in reply to Re^3: efficient determination of in/out of hours
in thread efficient determination of in/out of hours including Bank Holidays

The core of the problem is that I am incorrectly storing bank holiday start points in epoch seconds based on UTC0. Of course they actualy start at localtime == 00:00:00. I think I need to revise the code to store bank hols as (YYYY-1900):MM:DD, then compare to the appropriate fields of locatime($epoch).

original node updated with fixed code.

Cheers,
R.

Pereant, qui ante nos nostra dixerunt!

Replies are listed 'Best First'.
Re^5: efficient determination of in/out of hours
by soonix (Canon) on Oct 18, 2013 at 10:31 UTC

    You either need a mktime that is time zone aware (POSIX::mktime seems to know about DST but not about time zones), or an UTC variant, e.g. Time::timegm. Of course, the logic of $today instead of time needs to be applied, anyway. (I tried it out, seems to work)

    In the tests, the first date (from the future) kills too many holidays :-) (you should either sort the test data before the test, or create a new ooh() when time traveling)

    Update: The easiest fix would have been (in the originally posted version):

    my $today = POSIX::mktime(0,0,0,(localtime)[3..5]); while (<DATA>) { # read bank holiday file ...

      Even after working out $today in epoch, I still had the problem that I was storing bank hols as epoch. I would also need to look at each bank hol, and apply correct daylight saving time, before I could correctly establish its epoch start. I realised it was much easier to store bank hols as yyy:MM:DD and look at the date from localtime when I flip.

      I found another edge case around the transitions between saving/non saving. This could be bad as I may be treating alerts as OOH for an hour when the clocks go forward. I have added the following code to the main node to fix this

      $valid = POSIX::mktime(@start, $date, $mnth, $yr); $valid += $add * (24*60*60); # Check for daylight savings adjustment my $dst = $start[2] - +(localtime $valid)[2]; $valid += $dst * 60 * 60; my $now = time;

      Cheers,
      R.

      Pereant, qui ante nos nostra dixerunt!

Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://1058708]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others pondering the Monastery: (4)
As of 2024-04-25 23:28 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found