Logo ROOT   6.10/09
Reference Guide
exec1.C File Reference

Detailed Description

Echo object at mouse position.

Example of macro called when a pad is redrawn one must create a TExec object in the following way

TExec ex("ex",".x exec1.C");

this macro prints the bin number and the bin content when one clicks on the histogram contour of any histogram in a pad

void exec1()
if (!gPad) {
Error("exec1", "gPad is null, you are not supposed to run this macro");
int event = gPad->GetEvent();
if (event != 11) return;
int px = gPad->GetEventX();
TObject *select = gPad->GetSelected();
if (!select) return;
if (select->InheritsFrom(TH1::Class())) {
TH1 *h = (TH1*)select;
Float_t xx = gPad->AbsPixeltoX(px);
Float_t x = gPad->PadtoX(xx);
Int_t binx = h->GetXaxis()->FindBin(x);
printf("event=%d, hist:%s, bin=%d, content=%f\n",event,h->GetName(),binx,h->GetBinContent(binx));
Rene Brun

Definition in file exec1.C.