TChain Entry$

Hi,

I want to plot a value in a TChain versus the Entry number in the TChain.
Problem is that Entry$ is the entry number in a TTree not a TChain. Is there a way to have behaviour of Entry$ but refered to the TChain not the actual TTree in the loop?
If I do a TChain::Scan() there is a column named Row that is corresponding to what I want but I cannot refer it in a Draw formula.

Thanks

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Nicolas Produit
INTEGRAL Science Data Center  Phone:  +41 22 379 2140
16, Chemin d'Ecogia                            Fax:  +41 22 379 2133
CH-1290 Versoix                               www:    http://isdc.unige.ch/~produit