Helper class that updates and returns TTree branches as well as RDataFrame temporary columns.

Template Parameters

T	The type of the column

RDataFrame nodes must access two different types of values during the event loop: values of real branches, for which TTreeReader{Values,Arrays} act as proxies, or temporary columns whose values are generated on the fly. While the type of the value is known at compile time (or just-in-time), it is only at runtime that nodes can check whether a certain value is generated on the fly or not.

RColumnValue abstracts this difference by providing the same interface for both cases and handling the reading or generation of new values transparently. Only one of the two data members fReaderProxy or fValuePtr will be non-null for a given RColumnValue, depending on whether the value comes from a real TTree branch or from a temporary column respectively.

RDataFrame nodes can store tuples of RColumnValues and retrieve an updated value for the column via the Get method.

#include <ROOT/RDF/RColumnValue.hxx>

The documentation for this class was generated from the following file:

tree/dataframe/inc/ROOT/RDF/RColumnValue.hxx