Hi, It appears that you want B to be rows 1 thru 4, 6 thru 9, 11 thru 14 and 16 thru 17 from A. >B <- A[c(1:4, 6:9, 11:14, 16:17),] >E <- A[16:19,] -- View this message in context: http://r.789695.n4.nabble.com/create-new-matrices-with-specific-patterns-tp4702350p4702354.html Sent from the R help mailing list archive at Nabble.com.