Hi guys, Suppose I have an extremely large data frame with 2 columns and .5 mil rows. For example, the last 6 rows may look like this: . .. ... 89 100 93 120 95 125 101 NA 115 NA 123 NA 124 NA
I would like to manipulate this data frame to output a data frame that looks like:, 100 89, 93, 95 120 101, 115 125 123, 124 What would be the absolute quickest way to do this, given that there are many rows? Currently I have this: # m is the large two column data frame end <- na.omit(m[,'V2']); out <- data.frame(End=end, Start=unname(sapply(split(m[,'V1'],findInterval(m[,'V1'],end))[as.character(0:c(length(end)-1))],paste,collapse='.'))) However this is taking a little bit too long. Thank you for your help! [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.