Gain insights into R, the leading language for data analysis. Learn about its basics, advanced concepts, and practical coding to drive valuable insights from large datasets.

The digital world we live in has given companies and people access to staggering amounts of data, and anyone that can make use of that to drive valuable insights stands to benefit. The ability to work with large amounts of data is becoming a standard requirement for countless jobs across multiple industries.

Enter R, probably the most well-known language for data analysis. It's been used for years due to its robust statistical functionality, outstanding graphing ability, and extensibility through packages.

This interactive course will get you up to speed and assumes no prior knowledge of R. You'll start with the very basics and work your way up to advanced concepts like exception handling. By the time you're done, you'll be able to write detailed, useful code in R yourself.

Learn R from Scratch

## Problem Statement
Write a code that takes a list of numbers as input from `data.txt` file, finds the **mean** and **median** of those numbers, and outputs them on the `output/outData.txt` file.

### Input
A file `data.txt` containing a list of numbers.

### Output
A file `output/outData.txt` containing the mean and median of the input numbers.

### Sample Input
`data.txt`
```
3
8
1
```

### Sample Output
`output/outData.txt`
```
4
3
```
### Test Yourself
Write your code in the given area. If you get stuck, you can look at the solution.

mean <- function(myVector) # Creating function to find the mean
{
  # The formula for finding mean is sum / 2
  sum = 0 
  myOutputVector <- vector("integer", 0)
  for(i in myVector)
  {
    sum = sum + as.integer(i) # sum all the values in the vector
  }
  return(sum / length(myVector)) # return the mean
}

median <- function(myVector) # Creating function to find the median
{
  # median is the middle value of the sorted vector
  sortedVector=sort(as.integer(myVector)) # sort is a built in function. You can write your own soretd function as well
  myVectorLength = length(myVector)
  middle = myVectorLength / 2
  if (myVectorLength%%2==0)
  {
    return((sortedVector[middle]+sortedVector[middle+1])/2)
  }
  else
  {
    return(sortedVector[ceiling(middle)])
  }
}

# Driver Code
path <- "data.txt" # path of the input file
fileData <- file(path, open = "r") # open the file
lines <- readLines(fileData) # read all the lines present in the file

myVector <- vector("numeric", 0) # create empty vector to save all values
for (i in 1:length(lines))
{
  myVector <- c(myVector, lines[i]) # concatenate the values in this vector
}

result <- vector("numeric", 0) # create empty vector to store the result
myMedian = median(myVector) # find median
myMean = mean(myVector) # find mean

result <- c(result, myMean) # concatenate mean and median in the result
result <- c(result, myMedian)

write(result, "output/outData.txt") # write the result in the respective file

---
Let's look at the solution review of this challenge in the next lesson.

# Problem Statement
Write a code that takes a list of numbers as input from `data.txt` file, finds the **mean** and **median** of those numbers, and outputs them on the `output/outData.txt` file.

## Input
A file `data.txt` containing a list of numbers.

## Output
A file `output/outData.txt` containing the mean and median of the input numbers.

## Sample Input
`data.txt`
```
3
8
1
```

## Sample Output
`output/outData.txt`
```
4
3
```
## Test Yourself
Write your code in the given area. If you get stuck, you can look at the solution.

Given a file containing a list of numbers, output a file that contains the mean and median of those numbers.

Getting Started

Variables

Exploring R Objects

R Operators and Notation

Conditional Statements

Loops

Functions

Input/Output

Exception Handling

Classes

Fun Challenges

Conclusion

Challenge 2: Find Mean and Median

Problem Statement

Input

Output

Sample Input

Sample Output

Test Yourself