Hi, consider the following two dataframes: x1=c("232","3454","3455","342","13") x2=c("1","1","1","0","0") data1=data.frame(x1,x2)
y1=c("232","232","3454","3454","3455","342","13","13","13","13") y2=c("E1","F3","F5","E1","E2","H4","F8","G3","E1","H2") data2=data.frame(y1,y2) I need a new column in dataframe data1 (x3), which is either 0 or 1 depending if the value "E1" in y2 of data2 is true while x1=y1. The result of data1 should look like this: x1 x2 x3 1 232 1 1 2 3454 1 1 3 3455 1 0 4 342 0 0 5 13 0 1 I think a SQL command could help me but I am too inexperienced with it to get there. Thanks for your help! -- View this message in context: http://r.789695.n4.nabble.com/Creating-binary-variable-depending-on-strings-of-two-dataframes-tp3076724p3076724.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.