Matrix arithmetic in R Programming - Mini Project: Build & Apply

Matrix arithmetic

📖 Scenario: Imagine you work in a small company that tracks sales data in tables. Each table is a matrix where rows are products and columns are months. You want to do some basic math with these sales tables.

🎯 Goal: You will create two sales matrices, set a multiplier for a sales increase, multiply the matrices, and then print the result.

📋 What You'll Learn

Create two matrices with exact values

Create a multiplier variable

Multiply matrices using matrix multiplication

Print the resulting matrix

💡 Why This Matters

🌍 Real World

Matrix arithmetic is useful in business for analyzing sales data, financial modeling, and scientific calculations.

💼 Career

Many jobs in data analysis, finance, and engineering require working with matrices and performing matrix operations.

1

Create two sales matrices

Create a matrix called sales1 with values 1, 2, 3, 4, 5, 6 arranged in 2 rows and 3 columns, and another matrix called sales2 with values 7, 8, 9, 10, 11, 12 arranged in 3 rows and 2 columns.

R Programming

# Create sales1 and sales2 matrices with given values and dimensions
# Your code here

Need a hint?

Use the matrix() function with c() to combine values, and specify nrow and ncol.

2

Set a sales multiplier

Create a variable called multiplier and set it to 2 to represent doubling sales.

R Programming

sales1 <- matrix(c(1, 2, 3, 4, 5, 6), nrow = 2, ncol = 3)
sales2 <- matrix(c(7, 8, 9, 10, 11, 12), nrow = 3, ncol = 2)
# Create multiplier variable and set it to 2
# Your code here

Need a hint?

Just assign the number 2 to the variable multiplier.

3

Multiply matrices with multiplier

Create a new matrix called result by multiplying sales1 and sales2 using matrix multiplication, then multiply the result by multiplier.

R Programming

sales1 <- matrix(c(1, 2, 3, 4, 5, 6), nrow = 2, ncol = 3)
sales2 <- matrix(c(7, 8, 9, 10, 11, 12), nrow = 3, ncol = 2)
multiplier <- 2
# Multiply sales1 and sales2 using %*%, then multiply by multiplier and store in result
# Your code here

Need a hint?

Use %*% for matrix multiplication and multiply the whole result by multiplier.

4

Print the result matrix

Print the matrix result to display the final sales after multiplication.

R Programming

sales1 <- matrix(c(1, 2, 3, 4, 5, 6), nrow = 2, ncol = 3)
sales2 <- matrix(c(7, 8, 9, 10, 11, 12), nrow = 3, ncol = 2)
multiplier <- 2
result <- multiplier * (sales1 %*% sales2)
# Print the result matrix
# Your code here

Need a hint?

Use the print() function to show the matrix result.