Plot data file (3 columns) x,y, yerr

[Cristian_Sar]

Hello
I have data files of 3 columns, the first and second are values of energy and sensitivity and the third column corresponds to the error of the second column.

for example (randomfile.txt):
xval yval yerr
1 0.00334012 0.00004556
2 0.00071456 0.00345689
3 0.00235465 0.00006542
4 0 0
5 0 0
6 0.34508322 0.00125333

I use the command TGraphErrors * gr = new TGraphErrors (“randomfile.txt”, “% lg% lg% lg”); but visually in the graph the “bars” of the error are not visible because they are values of the third column are very small.

Is there any way to make these “bars” bigger? Any other way to graph and put the error bars? and last, how can I generate the % setting? or something similar.

I’d appreciate your help

[couet]

@Cristian_Sar

Is there any way to make these “bars” bigger?

The obvious answer will be to have larger values in your file. But then you will change your data … You can also go to log scale along the Y axis. Or stay linear and zoom around le Y value you want to enlarge .

[Wile_E_Coyote]

You could “multiply” errors by a factor 10 or 100 and then in the picture caption say that they were scaled by this factor.