Zooming TPaletteAxis range and changing color

ROOT
1

Dear all,

i have a TH2F with z values from 0 to 1 and i would like to draw it with "colz"
but with a palette from say 0.5 to 1. I change the palette axis changing the Z-axis range to 0.5-1 but then i get the palette with the same colors that i would get in the 0-1 range. I mean: the 0.5 box is green in both case (palette style 1). Since i zoom because i want to put in better evidence the 0.5-1 range i would like to see colors rescaled to that range.
Is there a simple way to do that ?

Thanks and regards,
Max

2

You should change the histogram minimum and maximum not the palette axis.

3

ok thanks, but i get the same result: 0.5 is still green and not violet as it’s 0 without the zoom

Max

4

The palette always goes from the minimum to the maximum of the histogram and the entire palette is used. To change the colors used you should modify the palette as explained in the TColor class in the Reference Guide. If you want to compare several histograms with the same color range make sure they all have the same minimum and maximum.