Dealing with TRUE, FALSE, NA and NaN

Question

Here is a vector

a <- c(TRUE, FALSE, FALSE, NA, FALSE, TRUE, NA, FALSE, TRUE)

I\'d like a simple function that returns TRUE

Answer 1

Taking Ben Bolker's suggestion above you could set your own function following the is.na() syntax

is.true <- function(x) {
  !is.na(x) & x
}

a = c(T,F,F,NA,F,T,NA,F,T)

is.true(a)
[1]  TRUE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE  TRUE

This also works for subsetting data.

b = c(1:9)
df <- as.data.frame(cbind(a,b))

df[is.true(df$a),]

  a b
1 1 1
6 1 6
9 1 9

And helps avoid accidentally incorporating empty rows where NA do exist in the data.

df[df$a == TRUE,]

      a  b
1     1  1
NA   NA NA
6     1  6
NA.1 NA NA
9     1  9