Questions about TTree::Draw()

Mark Boulay (mgb@owl.phy.queensu.ca)
Mon, 10 Aug 1998 13:46:40 -0400 (EDT)

Dear root team,
I have a couple of questions about using TTree:Draw().
First, I am wondering if it possible to produce a TTree containing
a TClonesArray branch, with some events having this array filled,
and others with an empty TClonesArray, and still use the TTree::Draw()
command for data contained in the TClonesArray. I have a tree with these
characteristics, and can retrieve events with TTree::GetEvent(), but
using TTree::Draw() for data in the TClonesArray causes root to hang.
The second (unrelated) question I have is about the autoscaling
of axies for TTree::Draw(). Is is possible to have the entire range
of the data in the tree scanned before choosing the axis scaling? It
now seems that a small number of events are sampled to choose the scale.

Thanks in advance for your help,
Mark.

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= =
= Mark Boulay =
= Department of Physics phone/voice mail: (613) 545-6861 =
= Queen's University fax: (613) 545-6813 =
= Kingston, Ontario email: mgb@sno.phy.queensu.ca =
= Canada, K7L 3N6 =
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