R Syntax Review

Using R Like a Calculator

Compute the square root of 1000. Answer

sqrt(1000)

[1] 31.62278

Write an expression that will return the area of a circle with radius = 2. Answer

Hint: circle area = pi * r squared

pi * 2 ^ 2

[1] 12.56637

Create a variable named x, and assign it a numeric value. Then write an expression that returns the circumference of a circle with radius = x. Answer

Hint: circumference of a circle = 2 x pi x radius

x <- 3

# circle circumference: 
2 * pi * x

[1] 18.84956

Create two numeric variables and add them together. Answer

x <- 1
y <- 2
x + y

[1] 3

What happens if you add a number variable to a character variable? Answer

x <- 1
y <- "bandana"
# x + y

NOTE: YOU WON’T BE ABLE TO SAVE A R NOTEBOOK THAT HAS CODE CHUNKS THAT PRODUCE ERRORS. COMMENT OUT ANY LINES OF CODE THAT GENERATE ERRORS BEFORE PROCEEDING.

Syntax Rules

Fix this code (uncomment it first). Answer

r <- 10

# circle_diameter <- R * 2
circle_diameter <- r * 2

# circle_area >- pi * r ^ 2
circle_area <- pi * r ^ 2

End

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