How to count TRUE values in a logical vector

Question

In R, what is the most efficient/idiomatic way to count the number of TRUE values in a logical vector? I can think of two ways:

z <- sample(c         


        

Answer 1

Another option is to use summary function. It gives a summary of the Ts, Fs and NAs.

> summary(hival)
   Mode   FALSE    TRUE    NA's 
logical    4367      53    2076 
>