Logo ROOT  
Reference Guide
graph.C File Reference

Detailed Description

View in nbviewer Open in SWAN Draw a simple graph.

void graph() {
TCanvas *c1 = new TCanvas("c1","A Simple Graph Example",200,10,700,500);
c1->SetGrid();
const Int_t n = 20;
Double_t x[n], y[n];
for (Int_t i=0;i<n;i++) {
x[i] = i*0.1;
y[i] = 10*sin(x[i]+0.2);
printf(" i %i %f %f \n",i,x[i],y[i]);
}
TGraph *gr = new TGraph(n,x,y);
gr->SetLineColor(2);
gr->SetLineWidth(4);
gr->SetMarkerColor(4);
gr->SetMarkerStyle(21);
gr->SetTitle("a simple graph");
gr->GetXaxis()->SetTitle("X title");
gr->GetYaxis()->SetTitle("Y title");
gr->Draw("ACP");
// TCanvas::Update() draws the frame, after which one can change it
c1->Update();
c1->GetFrame()->SetBorderSize(12);
c1->Modified();
}
Author
Rene Brun

Definition in file graph.C.

n
const Int_t n
Definition: legend1.C:16
TGraph::SetTitle
virtual void SetTitle(const char *title="")
Change (i.e.
Definition: TGraph.cxx:2324
TGraph::Draw
virtual void Draw(Option_t *chopt="")
Draw this graph with its current attributes.
Definition: TGraph.cxx:760
Int_t
int Int_t
Definition: RtypesCore.h:45
sin
double sin(double)
x
Double_t x[n]
Definition: legend1.C:17
TGraph::GetYaxis
TAxis * GetYaxis() const
Get y axis of the graph.
Definition: TGraph.cxx:1636
TGraph::GetXaxis
TAxis * GetXaxis() const
Get x axis of the graph.
Definition: TGraph.cxx:1626
gr
TGraphErrors * gr
Definition: legend1.C:25
y
Double_t y[n]
Definition: legend1.C:17
TNamed::SetTitle
virtual void SetTitle(const char *title="")
Set the title of the TNamed.
Definition: TNamed.cxx:164
Double_t
double Double_t
Definition: RtypesCore.h:59
TGraph
Definition: TGraph.h:41
TCanvas
Definition: TCanvas.h:23
graph
Definition: graph.py:1
c1
return c1
Definition: legend1.C:41