Convert negative values to zero in dataframe in R

Question

I have a dataframe in R that I would like to convert all columns (outside the ids) from negative to zero

id1  id2  var1  var2  var3
-1   -1   0     -33     5         


        

Answer 1

You could use pmax:

dat <- data.frame(id1=c(-1,-1), id2=c(-1,-2), var1=c(0,9), var2=c(-33,10), var3=c(5,-1))
dat[,-c(1,2)] <- matrix(pmax(unlist(dat[,-c(1,2)]),0), nrow=nrow(dat))