?ifelse df$newCol <- ifelse(is.na(df$col3), df$col1, df$col3)
On Wed, Sep 8, 2010 at 2:17 PM, Jakob Hedegaard <jakob.hedega...@agrsci.dk> wrote: > Hi list, > > I have a data frame (m) with 169221 rows and 10 columns and would like to > make a new column containing the content of column 3 but replace the NAs in > column 3 with the data in column 1 (from the same row as the NA in column 3). > Column 1 has data in all rows. > > My first attempt was: > > for (i in 1:169221){ > if (is.na(m[i,3])==TRUE){ > m[i,11] <- as.character(m[i,1])} > else{ > m[i,11] <- as.character(m[i,3])} > } > > Works - but takes too long time. > I would appreciate alternative solutions. > > Best regards, Jakob > > ______________________________________________ > 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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? ______________________________________________ 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.