[For this exercise, first write down your answer, without using R. Then, check your answer using R.] Answers to the exercises are available here. Exercise 1 If M=matrix(c(1:10),nrow=5,ncol=2, dimnames=list(c(‘a’,’b’,’c’,’d’,’e’),c(‘A’,’B’))) What is the value of: M Exercise 2 Consider the matrix M, What is the value of: M[1,] M[,1] M[3,2] M[‘e’,’A’] Exercise 3 Consider the matrix […]

# arrays and matrices

## Matrix Operations Exercises

This set of exercises will help you to learn and test your skill in matrix operations, starting with basic ones like scalar multiplication all the way through eigenvalue and eigenvectors. Before proceeding, it might be helpful to look over the help pages for the diag, t, eigen, and crossprod functions. If you want further documentation […]

## Bind exercises

Binding vectors, matrices and data frames using rbind and cbind is a common R task. However, when dimensions or classes differ between the objects passed to these functions, errors or unexpected results are common as well. Sounds familiar? Time to practice! Answers to the exercises are available here. Exercise 1 Try to create matrices from […]

## Array exercises

Exercise 1 Create an array (3 dimensional) of 24 elements using the dim() function. Exercise 2 Create an array (3 dimensional) of 24 elements using the array() function. Exercise 3 Assign some dimnames of your choice to the array using the dimnames() function. Exercise 4 Assign some dimnames of your choice to the array using […]

## Matrix exercises

Please note, solutions are available here. Exercise 1 Create three vectors x,y,z with integers and each vector has 3 elements. Combine the three vectors to become a 3×3 matrix A where each column represents a vector. Change the row names to a,b,c. Think: How about each row represents a vector, can you modify your code […]