H1->Reset() in 2D case

From: KOSU_FOKIN@garbo.lucas.lu.se
Date: Tue Oct 12 1999 - 19:33:26 MEST


Hello again,

I found a strange feature while drawing 2D histograms :

root [23] chain->Draw("f1e:f1de","","",10000);
root [24] chain->Draw("f1e:f1de","","",10);   
root [25] chain->Draw("f1e:f1de>>hist","","",10000);
root [26] chain->Draw("f1e:f1de>>hist","","",10);   

Lines [25] and [26] produce identical pictures where (visible) number of dots is the
same for both figures, while Nent = 10 and 10000 in these two cases (also displayed
in statistic box).

Lines [23] and [24] work fine showing different number of scattered dots (as expected).

Also I get into the same troubles if I call hist->Reset() for a 2D. 
It resets statistics but if I call 

root [27] hist->Draw() 
root [28] hist->Reset() 
root [29] hist->Draw()
root [30] hist->Fill(10,10)
(Int_t)43
root [31] hist->Draw()

[27] displays a number of scattered dots, [29] displays a blank histogram, 
but [31] displays a number of dots ([27]) again. It looks like cells are not set to 
zero ...

Did I miss something?

This runs under root 2.21. Sorry, it's not updated to 2.22 by our sysadmin yet but I
have not seen any reference to this feature in 2.22 development notes.

Best regards,
Anton 



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