TGraph and modify input quantities

ROOT
1

Hi,
i’m using this TGraph constructor

TGraph(const char *filename, const char *format, Option_t *)

(and the corresponding TGraphErrors)
in order to read data present on a text file. However i would like sometime to perform some modifications to one of the column that is going to be read. Is there a way to do so during the readout procedure?
Example: if i have 3 column on the text file i would like to multiply column 3 by column 2 and divide by a constant.

Thanks in advance,
Marco

2

No, this is not possible. Supporting this type of extension would imply that quickly somebody will request the possibility to phone his girl/boy friend when a "++ sign is found in the 3rd column ::slight_smile:

It is simpler to loop yourself on each line of the text file and call TGraph::SetPoint.

Rene

3

Funny example Rene, thanks.
I’ll stick with you suggestion.

Cheers,
Marco