In programming, you often need to know if an expression is true or false.
You can evaluate any expression in R, and get one of two answers, TRUE
or FALSE
.
When you compare two values, the expression is evaluated and R returns the logical answer:
10 > 9 # TRUE because 10 is greater than 9
10 == 9 # FALSE because 10 is not equal to 9
10 < 9 # FALSE because 10 is greater than 9
Try it Yourself »
You can also compare two variables:
You can also run a condition in an if
statement, which you will learn much more about in the if..else chapter.
a <- 200
b <- 33
if (b > a) {
print ("b is greater than a")
} else {
print("b is not greater than a")
}
Try it Yourself »
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