+TH2S* AliTRDCalibraVdriftLinearFit::AddAll()
+{
+ //
+ // return pointer to TH2S of all added histos
+ //
+
+ TH2S *histo = 0x0;
+ for(Int_t k=0; k < 540; k++) {
+ TH2S * u = GetLinearFitterHistoForce(k);
+ if(k == 0) {
+ histo = new TH2S(*u);
+ histo->SetName("sum");
+ }
+ else histo->Add(u);
+ }
+
+ return histo;
+
+}
+//______________________________________________________________________________________