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

#Subtraction
54 - 23

## [1] 31

#Multiplication
1.5 * 23

## [1] 34.5

#Square Root

sqrt(15)

## [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

round(mean(scores), 2)

## [1] 73.28

#Find the Maximum and Minimum score

max(scores)

## [1] 100

min(scores)

## [1] 0

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

mean1 = round(mean(scores), 2)

length(scores[scores > mean1])

## [1] 7

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

new_scores <- c(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

x <- c(1,1,1)


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

y <- c(1,3,4,5,6,7,8,9,10)

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

n <- c(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