built a lower triangular matrix from dataframe
Sorry, I just realized that it's not a lower triangualr matrix, but an upper triangular matrix! But still the solution/s should be rather similar in both cases. http://r.789695.n4.nabble.com/file/n4391127/matrix2.png I apologize for creating confusion... Nymphita -- View this message in context: http://r.789695.n4.nabble.com/built-a-lower-triangular-matrix-from-dataframe-tp4390813p4391127.html Sent from the R help mailing list archive at Nabble.com.