mx <- matrix(rep(rep(0L, 1000), 100), ncol = 100) index <- c(0, 500) for(i in seq(ncol(mx))) mx[index+i, i] <- 1
# check mx[c(1:5, 500:505), 1:10] # check apply(mx, 2, function(x) which(x == 1)) -- View this message in context: http://r.789695.n4.nabble.com/craeating-vectors-tp4736241p4736374.html Sent from the datatable-help mailing list archive at Nabble.com. _______________________________________________ datatable-help mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
