Re: dataframe implementations

[Jay Norwood via Digitalmars-d-learn]

One more discussion link on the NA subject. This one on the R 
implementation of NA using a single encoding of NaN, as well as 
their treatment of a selected integer value as a NA.

http://rsnippets.blogspot.com/2013/12/gnu-r-vs-julia-is-it-only-matter-of.html