Omit rows containing specific column of NA

Question

I want to know how to omit NA values in a data frame, but only in some columns I am interested in.

For example,

DF <- data.frame(x =          


        

Answer 1

Hadley's tidyr just got this amazing function drop_na

library(tidyr)
DF %>% drop_na(y)
  x  y  z
1 1  0 NA
2 2 10 33