Struggling to change to a log axis

Newbie
1

Hi,
I’m currently working on reproducing a graph (using TProfile) that displays the x-axis logarithmically as shown in the first attachment.

correct%20

wrong%20
wrong .png757×448 3.3 KB

which is labelled ‘correct’. However, when I use “canvas->SetLogx()”, the X-axis becomes logged but not in the way I would like.

I’ve been recommend to try to bin my data logarithmically but I’m not sure where to start with doing this. Is there an easier way of manipulating the x-axis to achieve this.

Thanks for any help :slight_smile:

2

Is the minimum x value equal to zero or negative ?

3

I’ve defined as starting from zero using:
TProfile* prof = new TProfile(“prof”, “prof”, 14, 0, 140 );

EDIT:
I’ve just changed in to a negative value and I observe the scale I want - Thanks for the quick help. Although if you can explain why this fixes it, that would be helpful.

4

I would rather do:

TProfile* prof = new TProfile(“prof”, “prof”, 14, 1., 140 );

to be conform to your model plot