First R program in R Programming

Introduction

We write a first R program to learn how to tell the computer what to do using R language.

When you want to see how R prints text on the screen.

When you want to check if your R setup is working.

When you want to learn the basics of R programming.

When you want to start practicing simple commands in R.

Syntax

R Programming

print("Hello, world!")

Use print() to show text or results on the screen.

Text must be inside quotes " " to tell R it is a message.

Examples

This prints the message Hello, world! on the screen.

R Programming

print("Hello, world!")

You can print any message by changing the text inside quotes.

R Programming

print("Welcome to R programming")

You can also print numbers without quotes.

R Programming

print(123)

Sample Program

This program prints a simple greeting message to show how R works.

R Programming

print("Hello, world!")

Important Notes

R shows [1] before the output to indicate the first item in the result.

Always use quotes for text messages in print().

You can run this program in RStudio or any R console.

Summary

The first R program uses print() to show messages.

Text messages must be inside quotes.

Running this program confirms your R setup works.

Practice

1. What does the print() function do in R?

easy

A. It saves the text to a file.

B. It displays the text or value inside the parentheses on the screen.

C. It creates a new variable.

D. It deletes existing data.

Solution

1. Step 1: Understand the purpose of print()

   The print() function is used to show output on the screen in R.

2. Step 2: Compare options

   Only It displays the text or value inside the parentheses on the screen. correctly describes that print() displays text or values.

3. Final Answer:

   It displays the text or value inside the parentheses on the screen. -> Option B

4. Quick Check:

   print() shows output = It displays the text or value inside the parentheses on the screen. [OK]

Hint: Remember: print() shows output on screen [OK]

Common Mistakes:

• Thinking print() saves to a file
• Confusing print() with variable creation
• Assuming print() deletes data

2. Which of the following is the correct syntax to print the message "Hello, R!" in R?

easy

A. print("Hello, R!")

B. print(Hello, R!)

C. print('Hello, R!)

D. print["Hello, R!"]

Solution

1. Step 1: Check the use of quotes

   Text messages must be inside matching quotes. print("Hello, R!") uses double quotes correctly.

2. Step 2: Verify function syntax

   print() requires parentheses, not square brackets. print("Hello, R!") uses parentheses correctly.

3. Final Answer:

   print("Hello, R!") -> Option A

4. Quick Check:

   Quotes + parentheses correct = print("Hello, R!") [OK]

Hint: Use matching quotes inside print() parentheses [OK]

Common Mistakes:

• Missing quotes around text
• Mismatched or missing closing quotes
• Using square brackets instead of parentheses

3. What will be the output of this R code?

print("Welcome to R programming")

medium

A. [1] "Welcome to R programming"

B. Welcome to R programming

C. Error: unexpected string

D. NULL

Solution

1. Step 1: Understand print() output format in R

   R prints output with an index [1] before the text when printing a character string.

2. Step 2: Match output with options

   [1] "Welcome to R programming" shows the correct R output format including the index.

3. Final Answer:

   [1] "Welcome to R programming" -> Option A

4. Quick Check:

   print() output includes [1] index = [1] "Welcome to R programming" [OK]

Hint: R shows [1] before printed strings [OK]

Common Mistakes:

• Ignoring the [1] index in output
• Expecting plain text without index
• Confusing output with error messages

4. Identify the error in this R code:

print('Hello R)

medium

A. Missing closing parenthesis

B. print() cannot print text

C. Mismatched quotes around text

D. Missing comma inside print

Solution

1. Step 1: Check quotes in the code

   The code starts with a single quote but does not close it properly, causing mismatched quotes.

2. Step 2: Verify parentheses

   The closing parenthesis is present, so the error is not missing parenthesis.

3. Final Answer:

   Mismatched quotes around text -> Option C

4. Quick Check:

   Quotes must match exactly = Mismatched quotes around text [OK]

Hint: Always close quotes properly inside print() [OK]

Common Mistakes:

• Ignoring missing quote errors
• Assuming parentheses are missing
• Thinking print() needs commas inside

5. You want to write a first R program that prints your name and age on separate lines. Which code will do this correctly?

hard

A. print("Name: Alice\nAge: 25")

B. print("Name: Alice")\nprint("Age: 25")

C. print("Name: Alice", "Age: 25")

D. print("Name: Alice")
print("Age: 25")

Solution

1. Step 1: Understand how to print multiple lines in R

   Using two separate print() calls prints on separate lines. The newline character \n inside a single print() prints \n literally, not a new line.

2. Step 2: Check code correctness

   print("Name: Alice") print("Age: 25") correctly uses two print() calls on separate lines with proper syntax.

3. Final Answer:

   print("Name: Alice") print("Age: 25") -> Option D

4. Quick Check:

   Separate print() calls for separate lines = print("Name: Alice") print("Age: 25") [OK]

Hint: Use separate print() calls for multiple lines [OK]

Common Mistakes:

• Using \n inside print() without escape
• Writing \n outside quotes causing syntax error
• Trying to print multiple lines in one print() without proper escape