Support for multidimensional arrays with TTreeReaderArray


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_ROOT Version: 6.16-6.20
_Platform: SL7, MacOS 10.15.3
_Compiler: gcc 4.8.5, Apple clang version 11.0.0 (clang-1100.0.33.17)


In a TTree that has a two-dimensional array:

*Br 6 :adc : adc[384][31]/I *
*Entries :68934 : Total Size= 3282483599 bytes File Size = 1090038445 *
*Baskets : 1340 : Basket Size= 25600000 bytes Compression= 3.01 *

MakeSelector skips the array:

root [13] W->MakeSelector(“foo”)
Warning in : Ingored branch adc because type is unknown.
(int) 0

(this is 6.16, the spelling was corrected in 6.18), although the legacy edition of MakeSelector works as before:

W->MakeSelector(“foo”,"=legacy")

Hi @haggerty,
sorry for the late reply. Indeed TTreeReader does not support multi-dimensional arrays. The legacy edition of MakeSelector is not based on TTreeReader iirc, so that would indeed explain what you are seeing.