Re: [ROOT] leap year problem with histogram class TH2F

From: reinhard sojka (reinhard@ripe.net)
Date: Fri Oct 26 2001 - 18:47:25 MEST


Hello Damir,

now I got it. 
I have to subtract 788918400 seconds from my Unix time stamp to convert it 
into a Root time stamp, right?

Thanks,
Reinhard 


 Damir Buskulic <buskulic@lapp.in2p3.fr> writes:
 * oops, no, it's always the same thing. The origin of root dates is 1st
 * January 1995 ! So the number of seconds you quote leaves you somewhere
 * in 2025.
 * To see it, add %Y to your time label format.
 * 
 * Cheers
 * 
 * Damir
 * 
 * Damir Buskulic wrote:
 * > 
 * > Hi Reinhard,
 * > 
 * > The time labels on axis are generated by standard C functions, namely
 * > strftime in this case. I must admit I trusted it when writing the code !
 * > I didn't check this leap year problem. It is probably the same for a
 * > leap century (every 400 years) but we have some time left for the next
 * > one !
 * > I'll see what I can do.
 * > 
 * > Damir
 * > 
 * > Reinhard Sojka wrote:
 * > >
 * > > Hi Rooters,
 * > >
 * > > there is a Problem with the labels on TH2F in  Version 3.01/06 (and olde
 * r).
 * > > When set to display month and day, February 29 is missing in every leap 
 * year.
 * > > The amount of displayed days seems to be ok.
 * > >
 * > > {
 * > > TH2F *h2 = new TH2F("h2", "test", 1500, 951436800, 951955200, 400, -400,
 *  400);
 * > > //2000
 * > > //TH2F *h2 = new TH2F("h2", "test", 1500, 825292800, 825724800, 400, -40
 * 0,
 * > > 400); //1996
 * > > h2->GetXaxis()->SetTimeDisplay(1);
 * > > h2->GetXaxis()->SetTimeFormat("%b %d");
 * > >
 * > > h2->Draw();
 * > > }
 * > >
 * > > Regards,
 * > > Reinhard
 * > 
 * > --
 * > =====================================================================
 * > | Damir Buskulic                  | Universite de Savoie/LAPP       |
 * > |                                 | Chemin de Bellevue, B.P. 110    |
 * > | Tel : +33 (0)450091600          | F-74941 Annecy-le-Vieux Cedex   |
 * > | e-mail: buskulic@lapp.in2p3.fr  | FRANCE                          |
 * > =====================================================================
 * > mailto:buskulic@lapp.in2p3.fr
 * 
 * -- 
 * =====================================================================
 * | Damir Buskulic                  | Universite de Savoie/LAPP       |
 * |                                 | Chemin de Bellevue, B.P. 110    |
 * | Tel : +33 (0)450091600          | F-74941 Annecy-le-Vieux Cedex   |
 * | e-mail: buskulic@lapp.in2p3.fr  | FRANCE                          |
 * =====================================================================
 * mailto:buskulic@lapp.in2p3.fr
 * 



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