Difference between revisions of "ROOT Tips and Tricks"
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== Add any useful code snippets, hints, tutorials, etc you use here! == | == Add any useful code snippets, hints, tutorials, etc you use here! == | ||
| + | </noinclude> | ||
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| + | How to save a graphical cut and implement it in another script: | ||
| + | |||
| + | 1. Make the plot | ||
| + | |||
| + | 2. Draw the graphical cut either by using the toolbar at the top of the screen under Edit->Toolbar->GraphicalCut (scissors), or by "hard-coding" it into your script, via: | ||
| + | |||
| + | //snipped; this code has the computer wait for you to draw the cut. | ||
| + | TCutG* cutg; | ||
| + | cutg=(TCutG*)gPad->WaitPrimitive("CUTG","CutG"); // making cut, store to CUTG | ||
| + | c1->Update(); //update the canvas | ||
| + | TCutG *tmpg, *mycutg; | ||
| + | tmpg = (TCutG*)gROOT->GetListOfSpecials()->FindObject("CUTG"); | ||
| + | mycutg = (TCutG*)(tmpg->Clone("mycutg")); | ||
| + | //NOTE: It is important to update the canvas where specified! | ||
| + | |||
| + | 3. Now, save as "mycut" (right-click on the cut->SetName) | ||
| + | |||
| + | 4. In command line: | ||
| + | $ TFile f("filename.root","recreate"); //reconstructs the cut | ||
| + | $ mycut.Write(); //saves the cut to "filename.root" | ||
| + | |||
| + | 4. In a new session/macro: | ||
| + | |||
| + | TFile f("filename.root"); | ||
| + | TCutG* mycut = (TCutG*)gRoot->FindObject("mycut"); | ||
| + | |||
| + | 5. Apply cut as you would if it were a TString. | ||
Latest revision as of 16:06, 20 July 2009
Add any useful code snippets, hints, tutorials, etc you use here!
How to save a graphical cut and implement it in another script:
1. Make the plot
2. Draw the graphical cut either by using the toolbar at the top of the screen under Edit->Toolbar->GraphicalCut (scissors), or by "hard-coding" it into your script, via:
//snipped; this code has the computer wait for you to draw the cut.
TCutG* cutg;
cutg=(TCutG*)gPad->WaitPrimitive("CUTG","CutG"); // making cut, store to CUTG
c1->Update(); //update the canvas
TCutG *tmpg, *mycutg;
tmpg = (TCutG*)gROOT->GetListOfSpecials()->FindObject("CUTG");
mycutg = (TCutG*)(tmpg->Clone("mycutg"));
//NOTE: It is important to update the canvas where specified!
3. Now, save as "mycut" (right-click on the cut->SetName)
4. In command line:
$ TFile f("filename.root","recreate"); //reconstructs the cut
$ mycut.Write(); //saves the cut to "filename.root"
4. In a new session/macro:
TFile f("filename.root");
TCutG* mycut = (TCutG*)gRoot->FindObject("mycut");
5. Apply cut as you would if it were a TString.
