codes for noise/baseline distribution. Plots are not correct

noise_performance/noise2.cpp

+void noise2(){
+  double row, col;
+  TCanvas* c1 = new TCanvas();
+  // std::string hist_name = "h" + std::to_string(row) + "_" + std::to_string(col);
+  TH2D* histo = new TH2D("histo", "Noise distribution",200,0.,255.,200,0.,255.);
+  
+  for (row = 0; row < 256; row++){
+    for(col = 0; col < 256; col++){
+      stringstream foldername, filename;
+
+       foldername << std::setw(3) << std::setfill('0') << row;
+       std::cout << " Foldername : " << foldername.str()<< std::endl;
+
+       filename << std::setw(3) << std::setfill('0') << row << "_"
+		<< std::setw(3) << std::setfill('0') << col << ".dat";
+       cout << "Filename : " << filename.str() << std::endl;
+
+     
+      
+      std::ifstream infile(foldername.str()+"/"+filename.str());
+      if(infile.is_open()){
+	std::cout<<"The data file  is opened..."<<std::endl;
+	 std::string line;
+	 double avr=0.,rms=0.;
+	 
+	 while(!infile.eof()){
+	   std::getline(infile,line);
+	   if(line.rfind("#",0)!=0){
+	     continue;
+	   }
+	   //  cout<<"original line : " <<line<<std::endl;
+	   std::string newline = " ";
+	   for(int i=0;i<line.length();i++){
+	     if(line[i]!=':'){
+	       newline=newline+line[i];
+	     }
+	     else{
+	       newline=newline+line[i]+" ";
+	     }
+	   }
+
+	   // cout<<"The new line with spaces " <<newline<<std::endl;
+      
+	   std::stringstream s;
+	   s<<newline;
+	   //cout<<"The line is stored in the stringstream object..."<<std::endl;
+	   string temp;
+	   double num=0.;
+	   double arr[2]={ };
+	   int i=0;
+	   while(!s.eof()){
+	     s>>temp;
+	     if(std::stringstream(temp)>>num){
+	       //cout<<num<<std::endl;
+	       arr[i] =num;
+	       i++;
+	     }
+	     temp = " ";
+	   }
+	   avr = arr[0];
+	   rms = arr[1];
+	 }
+
+	 cout << " avr : " << avr << " " << " rms : " << rms << std::endl;
+	 histo->Fill(row,col,rms);
+      }
+      else{
+	cout<<"Error..."<<std::endl;
+      }
+    }
+  }
+
+  histo->GetXaxis()->SetTitle("Row");
+  histo->GetYaxis()->SetTitle("Column");
+  histo->GetZaxis()->SetTitle("Baseline");
+  
+  histo->Draw("colz");
+}