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

54-15

## [1] 39

1.5*15

## [1] 22.5

54/23

## [1] 2.347826

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)

average

## [1] 73.27778

#Find the Maximum and Minimum score

maxs <- max(scores) 

maxs

## [1] 100

mins <- min(scores) 

mins

## [1] 0

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

high <- sum(scores > average)

high

## [1] 7

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

newscores <- scores[2:6]

Problem 3:

Read section 2.3, then answer the following questions

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

vector1 <- c(1, 1, 1, 1, 1)

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

vector2 <- c(1, 3, 5, 7, 9)

vector2

## [1] 1 3 5 7 9

# Create a vector by repeating a sequence from 1 to 3, 2 times. Print it.
vector3 <- c(1, 2, 3, 1, 2, 3)

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

class(mixed_vector)

## [1] "character"

## Coerce to numeric and print it 

as.numeric(mixed_vector)

## Warning: NAs introduced by coercion

## [1]  1 NA  3 NA  2

mixed_vector