TGaxis with decreasing values

Dear rooters,

I’m trying to produce a plot with an extra axis that has values of 180/x, where x is the original x-axis of the plot.
Here’s my first try:

As you can see, the topmost axis has all the numbers clustered together. I’m setting up the TGaxis in this way:

 TF1 *f1 = new TF1("f1","180/x",1.8,180);
 TGaxis *A1 = new TGaxis(1,5e-8,100,5e-8,"f1",510,"-");

Is there any setting that I should change to produce nice-looking, evenly spaced values of the TGaxis? Of course, I know that the 180/x dependence of the numbers will cluster the ticks at the beginning, what I mean is some way to skip values at the beginning and make the axis readable. I’ve been playing with ndiv but I can’t get it to work.
Thank you very much for your help!


There is not a lot of tuning you can do with this kind of axis (defined by a function). Nevertheless I will look at it and let you know.