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

# I picked 15 and 1.5 out of the set 

# Subtraction
15-1.5

## [1] 13.5

# Multiplication

15 * 1.5

## [1] 22.5

#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


sum(scores>round(mean(scores), 2))

## [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

my_vec <- rep(1,5)
print(my_vec)

## [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

seq(1,10, by= 2)

## [1] 1 3 5 7 9

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

rep(1:3, times = 3)

## [1] 1 2 3 1 2 3 1 2 3

Problem 4

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

# Check the class of the vector

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

## [1] "character"

## Coerce to numeric and print it 

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

numeric_version <-as.numeric(mixed_vector)

## Warning: NAs introduced by coercion

print(numeric_version)