Hi Andrzej, Currently, when a branch holds a variable of type integer, the histogram created has an integer bin size. However, the algorithm is not clever enough to recognize that Time-10008884 is also an integer. As soon as an expression is used, the bin size is assumed to be a float. You should create an histogram with the correct bin limits and bin size before calling TTree::Draw, then do: tree->Draw("Time-10008884>>myhist"); Rene Brun Andrzej Kupsc wrote: > > Hi, > In a tree I have a branch with C-time (secs>1970): > > tree->Branch("Time",&Time,"Time/i"); > > When I am plotting time vs other other variable say: > tree->Draw("x:Time") > The bins are much more coarse then in the case when time offset > was subtraced: > tree->Draw("x:(Time-1000883184)") > > There is not such big difference in automaticaly calculated bin > size when one dimensional plot is requested: > tree->Draw("Time") vs tree->Draw("Time-1000883184") > > I am using root 3.01/06 on RH7.0 > > Am I doing something wrong? > > Best regards > Andrzej Kupsc > --------------------------------------------------------------- > Address : The Svedberg Laboratory, > Uppsala University, Box 533, S-75121 Uppsala. > Telephone : +46-18-4713439 > Facsimile : +46-18-4713833 > e-mail : kupsc@unix.tsl.uu.se > ---------------------------------------------------------------
This archive was generated by hypermail 2b29 : Tue Jan 01 2002 - 17:51:00 MET