Document 'best practices' for ordering plot&selection definitions
Add a brief explanation on the construction of RDataFrame graph, and how to order them for efficient execution.
The very very brief version: most Define operations are done on-demand, so for refined selections (which take a frozen copy of the defined columns list when they are constructed) to take advantage of them, defining them later should be preferred, when practically possible. Same with forceDefine
: directly after constructing the selection is best.
Edited by Pieter David