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

Basic Syntax in R

R is a powerful language for data analysis and statistical computing. Below is a brief tutorial on basic syntax in R:

1. Variables and Assignment

To assign values to variables, we use the <- operator (though = can be used as well):

x <- 5
y <- "Hello, World!"

2. Basic Operations

Simple mathematical operations can be performed directly:

x + 5  # 10
x * 2  # 10
x / 2  # 2.5

3. Vectors

Vectors are sequences of elements. They can be created using the c() function:

v <- c(1, 2, 3, 4, 5)

Operations on vectors are often element-wise:

v + 2  # Adds 2 to each element

4. Functions

R has many built-in functions:

sum(v)  # 15
mean(v) # 3

To define your own function:

my_function <- function(a, b) {
  result <- a + b
  return(result)
}

5. Data Frames

Data frames are like tables and can be thought of as a list of vectors:

df <- data.frame(
  Names = c("Alice", "Bob", "Charlie"),
  Ages = c(25, 30, 35),
  Salaries = c(50000, 60000, 70000)
)

You can access columns using $:

df$Names

6. Control Structures

If-else:

if (x > 5) {
  print("Greater than 5")
} else {
  print("Not greater than 5")
}

For loop:

for (i in 1:5) {
  print(i)
}

While loop:

count <- 1
while (count <= 5) {
  print(count)
  count <- count + 1
}

7. Installing and Using Packages

You can install packages using:

install.packages("package_name")

Load them with:

library(package_name)

8. Importing Data

For a CSV file:

data <- read.csv("file_path.csv")

9. Basic Plotting

A simple plot can be made with:

plot(v, type="o", col="red", main="My Plot", xlab="X", ylab="Y")

This is a very brief introduction, and there is much more to learn in R. R has extensive documentation, and there are many online resources available to help further your understanding.

How to Write a Simple R Script:
Save the following code in a file with a .R extension, for example, myscript.R:
```
# This is a simple R script

# Print a message
print("Hello, World!")

# Perform a simple calculation
result <- 5 + 3
print(result)
```
You can run the script using the source function in R or by executing it in an R environment.

Variables and Assignments in R:

# Variable assignment
my_variable <- 42

# Print the variable
print(my_variable)

# Reassign the variable
my_variable <- my_variable + 10

Conditional Statements in R:

# If statement
my_condition <- TRUE

if (my_condition) {
  print("Condition is TRUE")
} else {
  print("Condition is FALSE")
}

Loops in R Programming:

For Loop:

# For loop
for (i in 1:5) {
  print(paste("Iteration:", i))
}

While Loop:

# While loop
count <- 1

while (count <= 5) {
  print(paste("Iteration:", count))
  count <- count + 1
}