(no subject)

From: Ijaz Ahmed <Ijaz.Ahmed_at_cern.ch>
Date: Thu, 23 Sep 2010 15:43:13 +0200

Hi....

I am getting the following error:

Error: illegal pointer to class object itsgraph 0x0 678 readQAgrid_tracks.C:506: *** Interpreter error recovered *

if somebody want to suggest me, here is the function:

---

void plotVertexTPC(Int_t axis){

  TFile f1("RunQA.root");

  TString labelsTPCITS[3];

  labelsTPCITS[0]="TPC Vertex_x";

  labelsTPCITS[1]="TPC Vertex_y";

  labelsTPCITS[2]="TPC Vertex_z";

  TGraphErrors *itsgraph = (TGraphErrors *)f1.Get(Form("fV%sMeanTPC",labelsTPCITS[axis].Data()));

---
line 506
    TCanvas *itstpc = new TCanvas( Form("Vertex_%s",labelsTPCITS[axis].Data()), Form("Vertex_%s",labelsTPCITS[axis].Data()),

                               0, 100+axis*50, 820, 620);

    if (itsgraph){
    itsgraph->Draw("apl");

    itsgraph->GetYaxis()->SetTitle(Form("vertex position in %s (cm)",labels[axis].Data()));

    delete itstpc;
   delete itsgraph;


}




}



Ijaz Ahmed
CIIT, Islamabad
mob#+923345349527
URL: http://iahmed.web.cern.ch/iahmed

Received on Thu Sep 23 2010 - 15:46:50 CEST