Spent the day porting an R implementation to C++. Guess how much time I save with the new implementation. A measly 12.5%. Le sigh.

#rstats hivemind: I am using an Rcpp::List on the C++ side as a POD and using push_back() to append new objects onto the end of it. The objects are unknown dimension Rcpp::IntegerMatrix and the number of objects that will go onto the Rcpp::List is unknown. Should I use a stack?

The problem is an unknown size unbalanced tree where each node is an unknown size matrix. I have a class for the matrix that writes to a Rcpp::IntegerMatrix. I can do the conversion up front and use the Rcpp::List for easy output or do the output conversion later.

Probably easiest to keep everything in a std::stack or std::vector and only populate an Rcpp::List at the very end for output.