Small speedup to reorder. Avoids memcpy call overhead.  Likely 5% improvement,  but could be up to 50% if data is already partially sorted or clustered.
Small speedup to reorder. Avoids memcpy call overhead.  Likely 5% improvement,  but could be up to 50% if data is already partially sorted or clustered.

vlulla/data.table,vlulla/data.table,Rdatatable/data.table,jangorecki/data.table,Rdatatable/data.table,vlulla/data.table,vlulla/data.table,Rdatatable/data.table,jangorecki/data.table,Rdatatable/data.table,jangorecki/data.table,jangorecki/data.table