Logarithmic contents in 3D histogram

Dear all,

I would like to set logarithmic scale on the content of a 3D histogram (I am using “BOX2Z” draw option) without setting any of the three axes to logarithmic scale.

In case of a 2D histogram I can use gStyle->SetLogz(), but this is not possible in this case since it changes both the color palette and the z axis to logarithmic.

Thank you!

It is true that there is no “4th axis” to the log scale on it. You can set the log scale on X Y and Z axis but not on the TH3 Content.

Maybe we can implement extra draw option for that - like logbox2.

Or something more generic that can be combined with the existing options for 3D histograms. Like "LOG3D"or “LOG3”.

But we do have only box draw option which make sense to combine with log content scale.

We have 4 different BOX options, ISO, and SCAT (even if it is deprecated). The new option will have to display the log of the content instead of the content itself. So all the options are concerned.

Thank you all for the replies and for considering my request: it would be a nice additional feature!

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I made first implementation of “logv” draw option for TH3 in JSROOT.

link and screenshot:

Volume of each box is proportional (with small offset) to log scale.

link and screenshot of same data with plain box2 drawing:

I also plan to extend “logv” usage for TH1 and TH2 histograms.
It will be alternative way yo configure log scale for content axis.