replace looped subsetVector with subsetDT (#5264)
replace looped subsetVector with subsetDT (#5264)


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