Introduction
Key elements of the visualization process
Environment - the R Language
14. NA value

Instruction

Sometimes the NA value is also applied to logical values. NA means "Not Available" and represents "no information for that value". For example, you don't know the age of the tiger in your zoo, so tigerAge <- NA. Also – and this happens more frequently – an error in your R code will produce an NA. When you see NA where a value should be, check your code for errors or missing information.

Exercise

We don't know the age of the tiger. See what R returns if you check whether a tiger is older than 5 years (tigerAge variable).

Press Run and Check Code button to see what happens.

Stuck? Here's a hint!

You should write:

tigerAge > 5