Coordinate systems in R Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a scatter plot using base R with x and y coordinates.

R Programming

plot(x, y, type = [1])

Drag options to blanks, or click blank then click option'

A"p"

B"l"

C"h"

D"b"

Attempts:

3 left

💡 Hint

Common Mistakes

Using type = "l" which draws lines instead of points.

Forgetting to put quotes around the type value.

In base R, type = "p" creates a scatter plot showing points.

2fill in blank

medium

Complete the code to convert Cartesian coordinates (x, y) to polar coordinates (r, theta).

R Programming

r <- sqrt([1]^2 + y^2)

Drag options to blanks, or click blank then click option'

Ax

Btheta

Cr

Dsin

Attempts:

3 left

💡 Hint

Common Mistakes

Using theta instead of x in the formula.

Confusing the radius r with the angle theta.

The radius r in polar coordinates is the square root of x^2 + y^2.

3fill in blank

hard

Fix the error in the code to calculate the angle theta in radians from Cartesian coordinates.

R Programming

theta <- atan2(y, [1])

Drag options to blanks, or click blank then click option'

Ar

Bsin

Cx

Dcos

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the order of x and y in atan2.

Using trigonometric functions like sin or cos incorrectly.

The atan2 function takes y first and then x, but in R it is atan2(y, x). Here, to get the angle, the first argument should be y and the second x. The code has the arguments reversed, so the blank should be x to fix the order.

4fill in blank

hard

Fill both blanks to create a data frame with polar coordinates from Cartesian vectors x and y.

R Programming

polar_coords <- data.frame(r = sqrt(x[1] + y[2]))

Drag options to blanks, or click blank then click option'

A^2

B+

C*2

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using multiplication *2 instead of exponentiation.

Using subtraction instead of addition.

To calculate radius r, square both x and y using ^2, then add them.

5fill in blank

hard

Fill all three blanks to convert polar coordinates (r, theta) back to Cartesian coordinates (x, y).

R Programming

x <- [1] * cos([2])
y <- [3] * sin(theta)

Drag options to blanks, or click blank then click option'

Ar

Btheta

Dx

Attempts:

3 left

💡 Hint

Common Mistakes

Using x instead of r in the formulas.

Swapping r and theta in the function arguments.

To convert polar to Cartesian, multiply radius r by cosine or sine of angle theta.