Homework 1

R Basics

You can insert an R code chunk into an R Markdown document by using a keyboard shortcut. The default keyboard shortcut to insert an R code is:

Windows/Linux: Ctrl + Alt + I Mac: Command + Option + I

Make sure to comment on your code using #

Problem 1:

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

.Subtraction .Multiplication .square root

1.5-15

## [1] -13.5

1.5*15

## [1] 22.5

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
length(scores[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]

Problem 3:

Read section 2.3, then answer the following questions

# Create a vector with the number 1 repeated 5 times. Print it
vector_one <- c(1,1,1,1,1)

# Create a vector with a sequence of numbers from 1 to 10 with a step of 2. Print it
vector_two <- c(1,3,5,7,9)

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

vector_three <- 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

## [1]  1 NA  3 NA  2

mixed_vector