<!-- TGraphErrors.md --- 
;; 
;; Description: 
;; Author: Hongyi Wu(吴鸿毅)
;; Email: wuhongyi@qq.com 
;; Created: 五 12月  5 11:52:37 2014 (+0800)
;; Last-Updated: 六 8月 13 12:34:41 2016 (+0800)
;;           By: Hongyi Wu(吴鸿毅)
;;     Update #: 2
;; URL: http://wuhongyi.cn -->

# TGraphErrors

## class


## code


## example

```cpp
//Draw a graph with error bars 带误差棒的图

TCanvas *c1 = new TCanvas("c1","A Simple Graph with error bars",200,10,700,500);

c1->SetFillColor(42);
c1->SetGrid();
c1->GetFrame()->SetFillColor(21);
c1->GetFrame()->SetBorderSize(12);

const Int_t n = 10;
Float_t x[n]  = {-0.22, 0.05, 0.25, 0.35, 0.5, 0.61,0.7,0.85,0.89,0.95};
Float_t y[n]  = {1,2.9,5.6,7.4,9,9.6,8.7,6.3,4.5,1};
Float_t ex[n] = {.05,.1,.07,.07,.04,.05,.06,.07,.08,.05};
Float_t ey[n] = {.8,.7,.6,.5,.4,.4,.5,.6,.7,.8};
TGraphErrors *gr = new TGraphErrors(n,x,y,ex,ey);
gr->SetTitle("TGraphErrors Example");
gr->SetMarkerColor(4);
gr->SetMarkerStyle(21);
gr->Draw("ALP");
```

<!-- TGraphErrors.md ends here -->