Hi, I 'd like to select the Date where myvalue =1800 appears the* first time*.
For instance: df =data.frame(date, myvalue, ...) ... Date myvalue 2012-01-05 2500 2012-01-06 2450 *2012-01-07 1800* 2012-01-08 2200 2012-01-09 1800 I'd like to retrieve the third line. I do not find a clean way. Thanks for your help -- View this message in context: http://r.789695.n4.nabble.com/dataframe-how-to-select-an-element-from-a-row-tp4311881p4311881.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list 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.