Homework 1

R Basics

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Problem 1:

From set = {1.5, 15, 0, 54, 23}, pick two numbers and perform the Following Operations:

.Subtraction .Multiplication .square root

# Pick two numbers from the set
num1 <- 15
num2 <- 1.5

# Perform subtraction
num1 - num2

## [1] 13.5

# Perform multiplication
num1 * num2

## [1] 22.5

# Find the square root of the two numbers
sqrt(num1)

## [1] 3.872983

sqrt(num2)

## [1] 1.224745

Problem 2

Suppose you have a set of numbers representing the assignments scores:

scores <- c(87,100, 91, 95, 81.5, 0, 39, 74, 92)

#Calculate the average of the scores, and round your answer to two decimal number

average <- mean(scores)
round(average, 2)

## [1] 73.28

# Find the Maximum and Minimum score

# Find the maximum score
max(scores)

## [1] 100

#Find the minimum score
min(scores)

## [1] 0

#Find how many scores were above the average, use coding for this

# Count how many scores are above the average
sum(scores > average)

## [1] 7

#Create a new set called new_scores that includes the elements from indices 2 to 6 of the scores vector

# Create a new set using scores from positions 2 through 6
new_scores <- scores[2:6]

# Print the new set
new_scores

## [1] 100.0  91.0  95.0  81.5   0.0

Problem 3:

Read section 2.3, then answer the following questions

# Create a vector with the number 1 repeated 5 times. Print it

# Repeat the number 1 five times
vector1 <- rep(1, 5)

# Print the vector
vector1

## [1] 1 1 1 1 1

# Create a vector with a sequence of numbers from 1 to 10 with a step of 2. Print it

# Create a sequence from 1 to 10, increasing by 2
vector2 <- seq(1, 10, by = 2)

# Print the vector
vector2

## [1] 1 3 5 7 9

# Create a vector by repeating a sequence from 1 to 3, 2 times. Print it.

# Repeat the sequence 1 through 3 two times
vector3 <- rep(1:3, 2)

# Print the vector
vector3

## [1] 1 2 3 1 2 3

Problem 4

mixed_vector <- c(1, "two", 3.0, TRUE, 2)

# Check the class of the vector
# Check the class of the vector 
class(mixed_vector)

## [1] "character"

## Coerce to numeric and print it 
# Coerce the vector to numeric
as.numeric(mixed_vector)

## Warning: NAs introduced by coercion