Unexpected behavior when using schema evolution

ROOT
1

Hello

I tried to use the new schema evolution which is a great new feature. Since I didn’ find a corresponding documentation I start to experiment with the schema evolution, but whatever I changed I couldn’t see any effect of the changes when checking the data with the TBrowser or the TreeViewer.

To simplify things I copied the example from the topic “Schema evolution rules not applied when loading from TTree” and modified things for my needs. Finaly I learned that when looping over the entries of a created tree using a library containing the new version of the example class in a macro I get the expected results after schema evolution. When starting a TBrowser and a TreeViewer in the same macro I only see the data written to
file with the old version of the example class.

Is this the expected behavior? I expect to see the data after schema evolution?

I attach my minimal working example to the topic.

Thanks

Florian
schemaEvolutionExample.tar.gz (2.33 KB)

2

Hi,

The TBrowser and TTreeViewer only show the physical branches in the TTree and thus would not show new data members:tree->Draw("exampleObjects.fPhi","","", 100, 0);does indeed work.

The fact that fRun is not updated correctly is indeed an over-sight. Could you submit a bug report in savannah so this issue tracked?

Thanks,
Philippe.

3

Hi,

Thanks for the explanation about the TBrowser and the TTreeViewer.

[quote]The fact that fRun is not updated correctly is indeed an over-sight. Could you submit a bug report in savannah so this issue tracked?
[/quote]

I will do this. Somehow fRun is not updated correctly only for tree->Draw. If i loop over the tree and extract the value for fRun everything is okay

Ciao

Florian