Y-axis resdual plot

ROOT
1

Hello, by this macro calocal.cpp (68.8 KB)

I can make a fit with the residual plot (notice that the macro produces many plots, but the plot whose I’m writing about is made by code at lines 1356-1413…i.e. the TCanvasa c19).

This is the obtained plot

image
image861×839 106 KB

I’ve two problems:

  1. As you can see, the y-axis of the residual plot has values too crowded and overlapping among them. Is it possible writing a lower number of values? For exampl currently the step is 0.2…is it possible to have a step 0.4? I.e. 0-0.4-0.8 etc??
    2.There are values out of the scale…how can I enlarge the scale?I wrote
    rp->GetLowerRefYaxis()->SetRange(-2.,2.);
    but it doesn’t work

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2

use SetNdivisions

h->GetYaxis()-> SetNdivisions(...)

SetRangeUser(-2.,2.);
3

Thank you @couet
Writing

rp->GetLowerRefYaxis()-> SetNdivisions(4);
rp->GetLowerRefYaxis()->SetRangeUser(-4.,4.);

I get this plot

image
image871×839 97 KB

given taht I setted

rp->GetLowerRefYaxis()-> SetNdivisions(4);

shouldn’t I have only -4,-2,0,2,4 values?

Here the updated macro
calocal.cpp (68.9 KB)

and the root file (if you need it) WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free

4

fit_results.txt is missing

5

Hello @couet it is generated by the macro to write the Chi2 and the Ndf values

6

Yes it does not seems possible to change the number of division of a Ratio Plot axis.
Can you open a issue with that?
Thanks.

7

Where should I do that?

8

By clicking on “New Issue” here: https://github.com/root-project/root/issues

9

Hello @couet here the issue https://github.com/root-project/root/issues/9172

10

Thanks,
I added a simple reproducer because your example is far too complex.

11

Yes, no problem!
I hope you will fix the bug

13

Indeed you should use:

   rp->GetLowYaxis()->SetNdivisions(2);

As shown is in the doc example.