Differences

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--- root:troubleshooting [2010/11/06 15:08] – decianm
+++ root:troubleshooting [2010/11/09 16:02] – nchiap
@@ Line 1: / Line 1: @@
-====== Troubleshooting in ROOT ======
+====== Writing Root-files ======
-===== Empty Files =====
+<code C>
-When you write a ROOT-file in a method with:
-<code>
-file->Write()
-</code>
-and the file exists, but is empty, check the right order of the files: Do
-<code>
 TFile* inputFile = TFile::Open("myInputFile.root");
 TFile* outputFile = new TFile("myOutputFile.root", "RECREATE");
@@ Line 12: / Line 6: @@
 outputFile->Write();
 </code>
-but don't
-<code>
+===== Empty Files =====
+When you get an an empty ROOT-file, check the right order of the files.
+Don't do
+<code C>
 TFile* outputFile = new TFile("myOutputFile.root", "RECREATE");
 TFile* inputFile = TFile::Open("myInputFile.root");
@@ Line 19: / Line 17: @@
 outputFile->Write();
 </code>
-===== Change Marker Style =====
-To change the marker style, you have to do:
-<code C++>
-TGraph* myGraph = TGraph();
-...
-myGraph->Draw();
-myGraph->SetMarkerStyle(20);
-</code>
-but it will not work if the marker style is set before the graph is drawn.
-as your file will be empty.

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