Hi, I have some statements like this, for ( UInt_t i = 0, i < N; i ++ ) { tree->Draw( "a : b", cut1 + cut2 ); if ( 0 < tree->GetSelectedRows() ) { htemp->Fit( "pol1", "q", "", 0.0, range ); } } which return Error: non class,struct,union object $htemp used with . or -> This only happens if the first "Draw" command of the loop does not return a positive number of entries. If I try TH1D * htemp = new TH1D(); before the loop, then all subsequent calls to htemp will point to this object which is unique from the default "htemp". The first problem I see is that cint wants to check the validity of the statements within the selection structure even if they will not be executed. The second, deeper issue is whether it is possible to explicitly instantiate default objects without roundabout statements like calling the "TTree::Draw" method to get the default histogram, "htemp". Justin
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