R Basics Exercise

We will test you on a few topics:

  • Basic Data Types
  • Basic Arithmetic
  • Vector
  • Vector Operations
  • Comparison operators
  • Vector Selection and Indexing

The exercises below should be straightforward if you've reviewed the lecture, don't expect something very challenging yet, this is more of a review to make sure you've understood everything so far! Later on exercises/projects will be more challenging (and a lot more fun!)

Solve the following problems using R

What is two to the power of five?

In [1]:
















Out[1]:




32
























 Create a vector called stock.prices with the following data points: 23,27,23,21,34 













In [4]:



    


















Out[4]:





    
	
  1. 23
    2. 
	
  2. 27
    3. 
	
  3. 23
    4. 
	
  4. 21
    5. 
	
  5. 34
    6. 



























 Assign names to the price data points relating to the day of the week, starting with Mon, Tue, Wed, etc...













In [6]:



    


















Out[6]:






	
Mon

		
23

	
Tues

		
27

	
Wed

		
23

	
Thu

		
21

	
Fri

		
34




























What was the average (mean) stock price for the week? (You may need to reference a built-in function) 













In [7]:



    


















Out[7]:




25.6
























 Create a vector called over.23 consisting of logicals that correspond to the days where the stock price was more than $23 













In [8]:



    
























 Use the over.23 vector to filter out the stock.prices vector and only return the day and prices where the price was over $23 













In [9]:



    


















Out[9]:






	
Tues

		
27

	
Fri

		
34




























 Use a built-in function to find the day the price was the highest













In [16]:



    


















Out[16]:




Fri: 34
























Okay that's it for the exercise on the basics! Great job!