Vector Operations

Part of the Fundamentals section of Coddy's R journey — lesson 59 of 78.

One of R's most powerful features is the ability to perform operations on entire vectors at once, without needing to loop through each element. This makes your code both cleaner and more efficient.

When you apply an arithmetic operator to a vector, R performs the operation on every element:

prices <- c(10, 25, 15, 30)
discounted <- prices * 0.9
print(discounted)

Output:

[1]  9.0 22.5 13.5 27.0

You can also perform operations between two vectors of the same length. R pairs up corresponding elements:

quantities <- c(2, 1, 4, 3)
prices <- c(10, 25, 15, 30)
totals <- quantities * prices
print(totals)

Output:

[1] 20 25 60 90

R provides useful built-in functions for common vector calculations like sum(), mean(), min(), and max():

scores <- c(85, 92, 78, 95, 88)
print(sum(scores))
print(mean(scores))
print(min(scores))
print(max(scores))

Output:

[1] 438
[1] 87.6
[1] 78
[1] 95

Challenge

Easy

You are provided with the following vectors:

hours_worked <- c(8, 7, 9, 6, 8)
hourly_rate <- c(15, 20, 18, 22, 17)

Perform the following operations and print each result:

Calculate the daily earnings for each day by multiplying hours_worked by hourly_rate (element-wise). Print this vector.
Apply a 10% bonus to all daily earnings (multiply by 1.1). Print the updated earnings vector.
Print the total earnings for the week using sum()
Print the average daily earnings using mean()
Print the highest single-day earnings using max()
Print the lowest single-day earnings using min()

Your output should be:

[1] 120 140 162 132 136
[1] 132.0 154.0 178.2 145.2 149.6
[1] 759
[1] 151.8
[1] 178.2
[1] 132

Cheat sheet

R performs operations on entire vectors at once without needing loops.

Applying an arithmetic operator to a vector performs the operation on every element:

prices <- c(10, 25, 15, 30)
discounted <- prices * 0.9
print(discounted)
# [1]  9.0 22.5 13.5 27.0

Operations between two vectors of the same length pair up corresponding elements:

quantities <- c(2, 1, 4, 3)
prices <- c(10, 25, 15, 30)
totals <- quantities * prices
print(totals)
# [1] 20 25 60 90

Common built-in functions for vector calculations:

scores <- c(85, 92, 78, 95, 88)
sum(scores)    # [1] 438
mean(scores)   # [1] 87.6
min(scores)    # [1] 78
max(scores)    # [1] 95

Try it yourself

# Given vectors
hours_worked <- c(8, 7, 9, 6, 8)
hourly_rate <- c(15, 20, 18, 22, 17)

# TODO: Write your code below

# 1. Calculate daily earnings (element-wise multiplication)

# 2. Apply 10% bonus to daily earnings

# 3. Print total earnings for the week using sum()

# 4. Print average daily earnings using mean()

# 5. Print highest single-day earnings using max()

# 6. Print lowest single-day earnings using min()