Web design

1. Input and Output in R
Programming
• Understanding how R interacts with users and
files for input and output operations.

2. Introduction
• Input and Output (I/O) are essential for
interacting with the user and external data
sources.
• • Input: To read data from the user or files.
• • Output: To display or save data.

3. Types of Input and Output
• Input:
• • Keyboard input
• • File input
• • Data frame import
• Output:
• • Console output
• • File output
• • Plot output

4. Keyboard Input Functions
• • readline(): Reads a line from the keyboard
• Example:
• name <- readline(prompt='Enter your name: ')
• print(paste('Hello', name))
• • scan(): Reads multiple numeric or character
inputs
• nums <- scan()
• print(nums)

5. Reading Data from Files
• • read.table():
• data <- read.table('data.txt', header=TRUE)
• • read.csv():
• csv_data <- read.csv('file.csv')
• • read_excel() (readxl library):
• library(readxl)
• excel_data <- read_excel('data.xlsx')

6. Writing Data to Files
• • write.table():
• write.table(data, 'output.txt', sep='t')
• • write.csv():
• write.csv(data, 'output.csv',
row.names=FALSE)

7. Output Display Functions
• • print(): Basic output
• print('Hello World')
• • cat(): Concatenate and print
• cat('The sum is:', 5 + 3, 'n')
• • message() and warning(): Display system
messages

8. File Handling Example
• data <- read.csv('input.csv')
• summary(data)
• write.csv(summary(data),
'summary_output.csv')

9. Plot Output
• • Saving plots:
• png('plot.png')
• plot(x, y)
• dev.off()

10. Summary
• • readline() and scan() for user input
• • read.csv(), read.table() for file input
• • print() and cat() for output
• • write.csv(), write.table() for saving data
• • Graphs saved using png() or pdf()

11. References
• • R Documentation: https://www.r-project.org
• • TutorialsPoint: R Input and Output
• • GeeksforGeeks: R Input/Output