[R] Apply function to one specific column / Alternative to for loop

[Stageexp]

Hi,
Try:
indx <- grep("Test",test_df[,1])  ##assuming that there is some pattern
 res <- within(test_df[-indx,],titel <- rep(test_df$titel[indx],
diff(c(indx,nrow(test_df)+1))-1))

## If you need to change the class

res[] <- lapply(res,function(x) if(any(grepl("[[:alpha:]]",x)))
as.character(x) else as.numeric(as.character(x)))


##Using data.frame(cbind()), etc. creates 


A.K.


This option worked great for me! I knew there was a nicer and much faster
way to solve this. One thing I already learned about R: Never use for-loops,
there is always a better way :-)



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