Test structure of dataframe in R

I have a simplified dataframe as follows:

test <- data.frame(
        x = c(1,2,3,NA,NA,NA),
        y = c(NA, NA, NA, 3, 2, NA),
        a = c(NA, NA, NA, NA, NA, TRUE)
        )

I want to test if when there’s NA in column x, there will always be a numeric value in column y AND when there’s a numeric value in column ‘x’, there will always be a NA in column y. How can I do that?

Thanks!

>Solution :

You can do:

(is.na(test$x) & is.numeric(test$y) & !(is.na(test$y))) |
  (is.na(test$y) & is.numeric(test$x) & !(is.na(test$x)))
#[1]  TRUE  TRUE  TRUE  TRUE  TRUE FALSE