Not!

One last operator to introduce is ! or, Not. You have already seen a similar operator, !=, so you might be able to guess what it does. Add ! in front of a logical expression, and it will flip that expression from TRUE to FALSE (and vice versa).

!TRUE
[1] FALSE

apple <- c(120.00, 120.08, 119.97, 121.88)

!(apple < 121)
[1] FALSE FALSE FALSE  TRUE

The stocks data frame is available for you to use.

This exercise is part of the course

Intermediate R for Finance

Exercise instructions

Use ! and a relational operator to know when ibm is not above 176.
A new vector, missing, has been created, which contains missing data.
The function is.na() checks for missing data. Use is.na() on missing.
Suppose you are more interested in where you are not missing data. ! can show you this. Use ! in front of is.na() to show positions where you do have data.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# IBM range
___

# Missing data
missing <- c(24.5, 25.7, NA, 28, 28.6, NA)

# Is missing?
___

# Not missing?
___

Edit and Run Code

This exercise is part of the course

Intermediate R for Finance

BeginnerSkill Level

4.8+

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