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

num_set <- c(1.5,15,0,54,23)
a <- 54
b <- 15

#subtraction
sub_result <- a-b
sub_result

## [1] 39

#Multiplication'
mult_result <- a*b
mult_result

## [1] 810

#Square root
sqrt_a <- sqrt(a)
sqrt_b <- sqrt(b)
sqrt_a

## [1] 7.348469

sqrt_b

## [1] 3.872983

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

## [1] 73.28

#Find the Maximum and Minimum score
max_score <- max(scores)
min_score <- min(scores)
max_score

## [1] 100

min_score

## [1] 0

#Find how many scores were above the average, use coding for this
above_avg_count <- sum(scores > avg_score)
above_avg_count

## [1] 7

#Create a new set called new_scores that includes the elements from indices 2 to 6 of the scores vector
new_scores <- scores[2:6]
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
vec1 <- rep(1,times=5)
print(vec1)

## [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
vec2 <- seq(from = 1, to = 10, by= 2)
print(vec2)

## [1] 1 3 5 7 9

# Create a vector by repeating a sequence from 1 to 3, 2 times. Print it.
vec3 <- rep(1:3,times =2)
print(vec3)

## [1] 1 2 3 1 2 3

Problem 4

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

# Check the class of the vector
class(mixed_vector)

## [1] "character"

## Coerce to numeric and print it 
numeric_vector <- as.numeric(mixed_vector)

## Warning: NAs introduced by coercion

print(numeric_vector)