R Tutorial
Fundamentals of R
Variables
Input and Output
Decision Making
Control Flow
Functions
Strings
Vectors
Lists
Arrays
Matrices
Factors
DataFrames
Object Oriented Programming
Error Handling
File Handling
Packages in R
Data Interfaces
Data Visualization
Statistics
Machine Learning with R
Vectors are the most basic data structure in R. They contain elements of the same type (e.g., numeric, character, or logical). This tutorial will walk you through various operations that can be performed on vectors in R.
You can create vectors using the c()
function:
vec <- c(1, 2, 3, 4, 5) print(vec)
You can access specific elements using indices:
print(vec[2]) # Prints the second element print(vec[c(1,4)]) # Prints the first and fourth elements
vec[1] <- 10 # Modify the first element vec[c(2,3)] <- c(11,12) # Modify the second and third elements
vec1 <- c(1, 2, 3) vec2 <- c(4, 5, 6) print(vec1 + vec2) # Element-wise addition print(vec1 - vec2) # Element-wise subtraction print(vec1 * vec2) # Element-wise multiplication print(vec1 / vec2) # Element-wise division
length(vec)
sum(vec)
prod(vec)
mean(vec)
var(vec)
sd(vec)
print(vec1 > 2) # Returns a logical vector: FALSE FALSE TRUE print(vec1 == 2) # Returns: FALSE TRUE FALSE
Many functions in R are vectorized, meaning they operate element-wise on vectors:
print(sqrt(vec1)) # Square root of each element print(abs(-vec1)) # Absolute value of each element
Generating sequences:
seq_vec <- seq(1, 10, by=2)
Repeating vectors:
rep_vec <- rep(vec1, times=3)
You can assign names to vector elements:
names(vec1) <- c("first", "second", "third") print(vec1)
Combine vectors using the c()
function:
combined_vec <- c(vec1, vec2)
sorted_vec <- sort(vec, decreasing=TRUE) # For descending order
For categorical variables, you can create factors:
gender <- c("Male", "Female", "Male", "Female") factor_gender <- as.factor(gender) print(factor_gender)
Vectors are a foundational data structure in R. Understanding how to create, manipulate, and perform operations on vectors is crucial for data analysis in R. Given their simplicity and power, vectors are often a starting point for many data manipulation tasks before proceeding to more complex data structures like data frames or matrices.
Element-wise operations on vectors in R:
Overview: Introduce element-wise operations on vectors, such as squaring each element.
Code:
# Element-wise operations on vectors my_vector <- c(1, 2, 3, 4) squared_vector <- my_vector^2 # Printing the squared vector print("Squared Vector:") print(squared_vector)
R vector addition and subtraction:
Overview: Demonstrate vector addition and subtraction in R.
Code:
# Vector addition and subtraction vector1 <- c(1, 2, 3) vector2 <- c(4, 5, 6) # Vector addition sum_vector <- vector1 + vector2 # Vector subtraction diff_vector <- vector1 - vector2 # Printing the results print("Vector1:") print(vector1) print("Vector2:") print(vector2) print("Vector Addition:") print(sum_vector) print("Vector Subtraction:") print(diff_vector)
Multiplying vectors in R programming:
Overview: Illustrate vector multiplication, both element-wise and dot product.
Code:
# Multiplying vectors in R vector1 <- c(1, 2, 3) vector2 <- c(4, 5, 6) # Element-wise multiplication elementwise_product <- vector1 * vector2 # Dot product dot_product <- sum(vector1 * vector2) # Printing the results print("Element-wise Product:") print(elementwise_product) print("Dot Product:") print(dot_product)
Vectorized operations in R with apply functions:
Overview: Discuss vectorized operations using apply functions like sapply
.
Code:
# Vectorized operations using apply functions my_vector <- c(1, 2, 3, 4) # Squaring each element using sapply squared_vector <- sapply(my_vector, function(x) x^2) # Printing the squared vector print("Squared Vector (sapply):") print(squared_vector)
Sorting and filtering vectors in R:
Overview: Demonstrate sorting and filtering operations on vectors.
Code:
# Sorting and filtering vectors in R my_vector <- c(3, 1, 4, 1, 5, 9, 2, 6) # Sorting in ascending order sorted_vector <- sort(my_vector) # Filtering values greater than 4 filtered_vector <- my_vector[my_vector > 4] # Printing the results print("Original Vector:") print(my_vector) print("Sorted Vector:") print(sorted_vector) print("Filtered Vector:") print(filtered_vector)
Vector concatenation and splitting in R:
Overview: Showcase vector concatenation and splitting using c()
and split()
functions.
Code:
# Vector concatenation and splitting in R vector1 <- c(1, 2, 3) vector2 <- c(4, 5, 6) # Concatenating vectors concatenated_vector <- c(vector1, vector2) # Splitting concatenated vector split_vector <- split(concatenated_vector, rep(1:2, each = 3)) # Printing the results print("Vector1:") print(vector1) print("Vector2:") print(vector2) print("Concatenated Vector:") print(concatenated_vector) print("Split Vector:") print(split_vector)