2-D Plot, COLZ option, expanding the color limits

ROOT
1

It appears that when plotting a 2D object using any of the options like
COL, COLZ that the minimum and maximum numerical values are based on the minimum and maximum within the cells themselves.

If I want to expand the color variance, ignoring the empty cells, is there a way of doing this?
Chris

2

[quote]
It appears that when plotting a 2D object using any of the options like
COL, COLZ that the minimum and maximum numerical values are based on the minimum and maximum within the cells themselves. [/quote]

Well, yes … by definition. The cells contents are mapped on the color palette. The histogram minimum is mapped on the first color in the palette and the histogram maximum on the last color in the palette. That’s how it is implemented.

I am not sure I understand your question. You can change the histogram minimum and maximum values using SetMinimum() and SetMaximum() … but I do not think that’s what you want …

3

It is always so incredibly difficult to verbalize my objective.

I’ve filled the cells, but the variance cell to cell is very small. I would like to rescale the colors such that the color index 0 is at the minimum cell value other than zero, and the maximum color index is at the maximum cell value.

I was trying to find the code that governs this but didn’t will setmin and setmax
on the histogram work?
Chris

4

So setting the histogram minimum ( h->SetMinimum() ) to something greater than 0 and close to the smallest non empty cell content should help. Doesn’t it ?

5

Sometimes the simple things evade me.
Thank you!
Chris