Just replied to this thread on r-help. Perhaps quite a few people might be unaware of syntax like this in data.table ...
http://r.789695.n4.nabble.com/Convert-the-output-of-by-to-a-data-frame-tp3268428p3278326.html Matthew _______________________________________________ datatable-help mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
