Drawing vars from a TTree

Nick van Eijndhoven (Nick@fys.ruu.nl)
Thu, 26 Jun 1997 10:08:42 +0200 (MET DST)

Dear ROOTers,
I have all my physics column wise ntuples now converted into root
files (i.e. trees) and would like to do the following :

* Draw variable A versus B with a weight W under the condition that C>D

In PAW I can do this by :

nt/plot 999.A%B W*(C.gt.D)

and in ROOT I tried :

Root> TChain q("h999")
Root> q.Add("test.root")
Root> q.Draw("A:B","W*(C>D)")

but when I inspected the produced 2-dim histo in Lego layout all
heights were at 0.

Question : How to achieve this in ROOT ?

Thanks,
Nick.
*----------------------------------------------------------------------*
Dr. Nick van Eijndhoven Department of Subatomic Physics
email : nick@fys.ruu.nl Utrecht University / NIKHEF
tel. +31-30-2532331 (direct) P.O. Box 80.000
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fax. +31-30-2518689 The Netherlands
WWW : http://www.fys.ruu.nl/~nick Office : Ornstein lab. 172
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