hello again, I have two sets of data, 1 = {A, B, C, D, E} and 2 = {F, G, H, I, J), and the figure is the same personof the the figure F , B is the same that G and so on until E = J. So I have to make about 200 combinations with two pictures of each group, forming a new group of four elements, with no repeating figures. The question is, how my good friend R can help me? a huge brazilian thanks, ----- pvm -- View this message in context: http://r.789695.n4.nabble.com/combining-from-two-samples-with-restrictions-tp3468002p3468002.html Sent from the R help mailing list archive at Nabble.com.