Instruction: Download and Install R and RStudio

Transcription

1 1 Instruction: Download and Install R and RStudio We will use a free statistical package R, and a free version of RStudio. Please refer to the following two steps to download both R and RStudio on your computer. 1. Download R from: To download R, please choose your preferred Comprehensive R Archive Network (CRAN) mirror. Click either on download R or on CRAN mirror both links will take you to the following page: Scroll down the page till you find Canada. Click on University of Toronto CRAN mirror to download R:

2 2 Download and install R. Click on your operating system (e.g., Windows): If you have a windows operating system and have clicked on: Download R for Windows, you will be directed to the page like the one below. The steps would be the same if you have a MAC operating system (please see the next page of this document and a YouTube video I find very straight forward to follow). Click on install R for the first time :

3 The Actual Download is as follows; Click on the Download R for Windows or the newest version! 3 If you have a MAC operating system and have clicked on: Download R for MAC (OS) X, you will be directed to the page like the one below. For what comes next regarding R download on MAC, please watch this YouTube Video (its first 1:30 minutes - the video shows how to download R and RStudio on MAC):

4 4 R is now downloaded on my computer (Windows operating system). Click on the R (R icon) to open R.

5 This is R Console. We can use R to do simple to complex calculations (R is more than just a calculator!). 5

6 See below for a short and simple calculation-based demo. Type in R console, where you see the red greater sign > 2+3. We should see the answer: 5 6 We can assign an operation to something. I assigned 2+3 to x. I called for x. I got 5 as the answer.

7 7 Important Note regarding R: R is sensitive to spelling (e.g., remember if you capitalized a word or a letter)

8 8 It is better to write operations (e.g., our codes, functions ) elsewhere and then run them. We can open New R Script (this will open an Untitled R Editor ): Go to File > New Script

9 In R editor window, type the following (this is an example): 3+4 y = 3+4 y Select all the above lines. 9

10 10 Right click (on your mouse) and select Run line or selection. See what has been outputted on R Console. Isn t this approach so neat? Why? Because you can save your untitled editor. That means, you can open your saved editor and run the codes again. We will see in R Studio as a demo.

11 11 Save your untitled editor: Go to File > Save as

12 12 Since you created a file that saved all your R code in it, just type q() in the R Console to exit R. You will be prompted with whether you want to save your work space or not. The benefit of saving your workspace would be that when open it later, you can use the up and down arrow from your keyboard to call the previous codes (or functions) that you used in that workspace. But since we save our written codes in a separate file, we don t need to save our R workspace. You can say No to this question.

13 13 2. Download RStudio from: Click on Download

14 Scroll down the page, and click on RStudio Desktop Download Now 14

15 15 Find and click on the installer for your machine (e.g., Windows, Mac): Because I have Windows 8.1, I selected the first installers option to download RStudio on my PC computer: If you have a MAC OS, select the second installers option to download RStudio on your MAC computer: For what comes next regarding RStudio download on MAC, watch this YouTube Video (its last 2 minutes - the video shows how to download R and RStudio on MAC): Important Notes: RStudio provides an integrated support for editing and executing R codes. Once you have RStudio downloaded on your computer, search for it!

16 16 In my computer, I clicked on the search icon, typed RStudio in it. My computer opened RStudio: Notice that RStudio divides its world into four panels: R Script (top left); R Console (bottom left); Plots (bottom right); Environment (Top right). One can certainly use R without using RStudio. RStudio makes a number of things easier. I highly recommend using RStudio Videos (Voice overs) regarding how to: Download R and RStudio on MAC OS (a YouTube Video):

17 17 Change the Default Working Directly in R Set Working Directory Permanently - in R Open RStudio in your computer. In R Console, type getwd() and run the code. R Console outputs your current working directory, a place that your installed R is currently expecting to read data from We can change the working directory permanently (we can always change it to something else). This is what my R Console outputs: > getwd() [1] C:/Users/user/Documents/ABC In the menu bar of R Studio, go to Tools > Global Options

18 18 Click on Browse to change your Default working directory to another location (folder in your computer)

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21 21 After clicking Ok, close R Studio Re-open R Studio In R Console, type getwd() This is what my R Console outputs > getwd() [1] "C:/Users/user/Documents/Rdata" *** Based on what you did above, you do not need to use the function setwd()***