Difference between revisions of "R/C2/Introduction-to-R-script/English"
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| − | + | '''Title of script''': Introduction to R script | |
| − | + | '''Authors''': Shaik Sameer (IIIT Vadodara) and Sudhakar Kumar (IIT Bombay) | |
| + | '''Keywords''': R, RStudio, script, video tutorial | ||
| − | {| | + | {| border =1 |
| − | + | |'''Visual Cue''' | |
| − | + | |'''Narration''' | |
| − | + | |- | |
| − | |- | + | || Show slide |
| − | || Show slide | + | |
Opening slide | Opening slide | ||
| − | || | + | || Welcome to this tutorial on '''Introduction to R script.''' |
| − | |- | + | |- |
|| Show slide | || Show slide | ||
Objectives | Objectives | ||
| − | || In this tutorial, | + | || In this tutorial, you will learn: |
| + | * How to work with an '''R script '''in '''RStudio''' | ||
| − | + | |- | |
| − | |- | + | |
|| Show slide | || Show slide | ||
Pre-requisites | Pre-requisites | ||
| − | + | || To understand this tutorial, you should know basic commands of '''R'''. | |
| − | + | ||
| − | || To understand this tutorial, you should know | + | |
| − | + | ||
| − | + | ||
| − | + | ||
If not, please locate the relevant tutorials on '''R''' on this website. | If not, please locate the relevant tutorials on '''R''' on this website. | ||
| − | |- | + | |- |
|| Show slide | || Show slide | ||
Systems requirements | Systems requirements | ||
| − | + | || This tutorial is recorded on | |
| − | + | * '''Ubuntu Linux OS 16.04''' | |
| − | || This tutorial is recorded on* | + | * '''R '''version''' 3.2.3 ''' |
| − | * | + | * '''RStudio''' version''' 1.1.456''' |
| − | * | + | |
| − | + | ||
| − | + | ||
| − | + | ||
Install '''R''' version '''3.2.0''' or higher. | Install '''R''' version '''3.2.0''' or higher. | ||
| − | |- | + | |- |
|| Show slide | || Show slide | ||
What is '''R script''' | What is '''R script''' | ||
| − | || * | + | || |
| − | * | + | * An '''R script''' is a plain '''text file''' in which you save your '''R code''' |
| + | * '''Script '''allows you to show your work to others, and also reproduce and modify the results | ||
| − | + | |- | |
| − | |- | + | |
|| Show slide | || Show slide | ||
Creating a folder for our project | Creating a folder for our project | ||
| − | || * | + | || |
| − | * | + | * Before you begin please create a folder named '''myProject '''on '''Desktop'''. |
| − | + | * I have already created this folder on my '''Desktop'''. | |
| − | + | * I shall now save all my '''scripts '''and '''data sets '''in this folder. | |
| + | * Later, I shall set this folder as my '''Working Directory'''. | ||
| − | + | |- | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | |- | + | |
|| [RStudio] | || [RStudio] | ||
RStudio window | RStudio window | ||
|| Let us switch to '''RStudio'''. | || Let us switch to '''RStudio'''. | ||
| − | |- | + | |
| + | |- | ||
|| [RStudio] | || [RStudio] | ||
| − | + | Highlight the tabs '''Untitled1 '''and '''R packages available''' in the '''Source '''window | |
| − | + | || We will close these two tabs named '''Untitled1 '''and '''R packages available'''. | |
| − | + | ||
| − | + | ||
| + | Click on the small cross symbol next to these tabs. | ||
|- | |- | ||
| − | | | + | || [RStudio] |
| − | + | ||
| + | Click on the green '''plus sign >> '''select '''R Script''' from the dropdown | ||
| + | || We will now create a new '''R script'''. | ||
| + | * In the top left corner of '''RStudio, '''click on the green '''plus sign. ''' | ||
| + | * Now from the dropdown menu, select '''R Script'''. | ||
| + | |||
| + | |- | ||
| + | || Highlight the new '''R''' '''script Untitled1''' | ||
| + | || A new '''R script''' appears in the '''Source''' window. | ||
You can also create a new '''R script''' by pressing '''Ctrl+Shift+N''' together. | You can also create a new '''R script''' by pressing '''Ctrl+Shift+N''' together. | ||
| − | |- | + | |- |
|| Click on '''File''' | || Click on '''File''' | ||
|| Let us save this '''R''' '''script''' first. | || Let us save this '''R''' '''script''' first. | ||
In the top left corner of the screen, click on the '''File''' option. | In the top left corner of the screen, click on the '''File''' option. | ||
| − | |- | + | |- |
|| Click on '''Save '''option | || Click on '''Save '''option | ||
|| Then click on '''Save''' to save the script. | || Then click on '''Save''' to save the script. | ||
| − | |- | + | |- |
| − | || Select the directory '''myProject'''>> type name | + | || Select the directory '''myProject'''>> type name '''myfirstscript'''>> click on '''Save '''button |
|| Select the directory where you want to save your '''R script'''. | || Select the directory where you want to save your '''R script'''. | ||
| − | I am saving | + | I am saving the '''script '''in the folder '''myProject''' on my '''Desktop''',''' '''with the name '''myfirstscript.''' |
Finally, click on the '''Save''' button. | Finally, click on the '''Save''' button. | ||
| − | |- | + | |- |
|| Point to '''myfirstscript.R '''in the '''Source '''window | || Point to '''myfirstscript.R '''in the '''Source '''window | ||
|| Now you can see that the file is named as '''myfirstscript.R'''. | || Now you can see that the file is named as '''myfirstscript.R'''. | ||
'''RStudio''' automatically adds '''dot R''' at the end of the filename. | '''RStudio''' automatically adds '''dot R''' at the end of the filename. | ||
| − | |- | + | |- |
|| | || | ||
|| Now, let us write some lines of code in the '''script''' file '''myfirstscript.R'''. | || Now, let us write some lines of code in the '''script''' file '''myfirstscript.R'''. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
'''testSample <- c(1,2,3,4)''' | '''testSample <- c(1,2,3,4)''' | ||
| − | |||
| − | |||
|| We will create a '''vector''' named '''testSample''' with one two three four as its '''elements'''. | || We will create a '''vector''' named '''testSample''' with one two three four as its '''elements'''. | ||
| − | |||
We have already learned how to create '''vectors''' earlier in this series. | We have already learned how to create '''vectors''' earlier in this series. | ||
| − | |||
In the '''Source '''window, type '''testSample''' space '''less than''' symbol.Now type '''hyphen space c 1 comma 2 comma 3 comma 4 '''in''' parentheses.''' | In the '''Source '''window, type '''testSample''' space '''less than''' symbol.Now type '''hyphen space c 1 comma 2 comma 3 comma 4 '''in''' parentheses.''' | ||
| − | |||
Press '''Enter. ''' | Press '''Enter. ''' | ||
| − | |- | + | |- |
|| Highlight '''<- symbol''' | || Highlight '''<- symbol''' | ||
|| You may also use '''equal''' sign in place of '''less than''' symbol followed by '''hyphen'''. | || You may also use '''equal''' sign in place of '''less than''' symbol followed by '''hyphen'''. | ||
| − | |- | + | |- |
|| Highlight '''Save''' icon | || Highlight '''Save''' icon | ||
| − | + | || In the '''Source '''window, to the left of the checkbox '''Source on Save, ''' click on the '''Save''' icon. | |
| − | + | ||
| − | || In the '''Source '''window, to the left of the checkbox '''Source on Save, ''' | + | |
| − | + | ||
| − | click on the '''Save''' icon. | + | |
Or, press '''Ctrl+S '''together to save the file. | Or, press '''Ctrl+S '''together to save the file. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
'''print(testSample)''' | '''print(testSample)''' | ||
|| We will now use the '''print function''' to display the values in '''testSample''' '''vector.''' | || We will now use the '''print function''' to display the values in '''testSample''' '''vector.''' | ||
| − | |||
In the '''Source '''window, type p r i | In the '''Source '''window, type p r i | ||
| − | |- | + | |- |
|| Highlight the predicted functions | || Highlight the predicted functions | ||
|| '''RStudio''' automatically starts suggesting different '''functions'''. | || '''RStudio''' automatically starts suggesting different '''functions'''. | ||
| − | |- | + | |- |
|| | || | ||
|| You can navigate this list of '''functions''' by using the '''up (↑)''' and '''down (↓)''' arrow keys on the keyboard. | || You can navigate this list of '''functions''' by using the '''up (↑)''' and '''down (↓)''' arrow keys on the keyboard. | ||
| − | |- | + | |- |
|| Press '''Enter''' | || Press '''Enter''' | ||
|| To select a particular '''function''', just press '''Enter'''. | || To select a particular '''function''', just press '''Enter'''. | ||
| − | |- | + | |- |
|| | || | ||
|| Finish typing''' print testSample '''in '''parentheses '''and press '''Enter'''. | || Finish typing''' print testSample '''in '''parentheses '''and press '''Enter'''. | ||
| − | |- | + | |- |
|| Press '''Ctrl+S ''' | || Press '''Ctrl+S ''' | ||
|| Now let’s save the file and '''run''' it with these two lines only. | || Now let’s save the file and '''run''' it with these two lines only. | ||
| − | |- | + | |- |
| + | || | ||
| + | || Now, we maximize the '''Source '''window. | ||
| + | |- | ||
|| [RStudio] | || [RStudio] | ||
| Line 174: | Line 161: | ||
You can see the line-by-line execution of the '''script''' in the '''Console'''. | You can see the line-by-line execution of the '''script''' in the '''Console'''. | ||
| − | |||
You can also run the '''script '''by pressing '''Ctrl+Shift+Enter together'''. | You can also run the '''script '''by pressing '''Ctrl+Shift+Enter together'''. | ||
| − | |||
For this, you need to first click in the '''script '''window. | For this, you need to first click in the '''script '''window. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
| − | '''firstVar''' ''' | + | '''firstVar''' '''= 10''' |
|| Now let’s declare a '''variable firstVar''' with value of ten''' '''in the '''Source''' window. | || Now let’s declare a '''variable firstVar''' with value of ten''' '''in the '''Source''' window. | ||
| − | |||
Type''' firstVar''' with capital V space '''equal''' sign space 10 and press '''Enter. ''' | Type''' firstVar''' with capital V space '''equal''' sign space 10 and press '''Enter. ''' | ||
| − | |- | + | |- |
|| | || | ||
|| Please note that '''R''' language is case-sensitive. | || Please note that '''R''' language is case-sensitive. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
| Line 197: | Line 181: | ||
|| We will now use the '''print function '''to show the value of '''firstVar'''. | || We will now use the '''print function '''to show the value of '''firstVar'''. | ||
| + | In the '''Source '''window, type '''print'''. | ||
| − | + | I am typing only '''p r i n '''but the options appear and I select '''print '''from there. Now in '''parentheses''', start typing '''firstVar. ''' | |
| − | + | ||
| − | + | ||
| − | + | ||
| + | '''RStudio''' shows '''firstVar'''; press '''Enter''' to select it. | ||
Press '''Enter''' to go to the next line. | Press '''Enter''' to go to the next line. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
| Line 211: | Line 194: | ||
'''print(secondVar)''' | '''print(secondVar)''' | ||
| − | || | + | || Now let’s declare another '''variable secondVar''' with value of fifteen. |
| − | + | ||
In the '''Source''' window, type''' secondVar''' space '''equal''' sign space 15 and press '''Enter'''. | In the '''Source''' window, type''' secondVar''' space '''equal''' sign space 15 and press '''Enter'''. | ||
| − | + | Now, as shown before, type '''print''' '''secondVar''' in '''parentheses''' to show its value and press '''Enter''' . | |
| − | Now, as shown before, type '''print''' '''secondVar''' in '''parentheses''' to show its value and press '''Enter''' | + | |- |
| − | |- | + | |
|| | || | ||
| − | || We can add '''comments''' to our code by using ''' | + | || We can add '''comments''' to our code by using '''# hash '''symbol followed by our '''comment'''. |
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
| − | ''' | + | '''# Creating an R script''' |
Highlight the comment line and first line of code | Highlight the comment line and first line of code | ||
| Line 232: | Line 213: | ||
Please make sure that your '''comment''' and the first line of code appear in separate lines. | Please make sure that your '''comment''' and the first line of code appear in separate lines. | ||
| − | |- | + | |- |
|| Click on the line '''print(secondVar)''' | || Click on the line '''print(secondVar)''' | ||
|| Now, let’s '''comment''' the line '''print(secondVar)'''. | || Now, let’s '''comment''' the line '''print(secondVar)'''. | ||
To do that, first click on this line. | To do that, first click on this line. | ||
| − | |- | + | |- |
|| from '''Code '''option >> | || from '''Code '''option >> | ||
| Line 246: | Line 227: | ||
This option helps us to '''comment''' as well as '''uncomment''' a line. | This option helps us to '''comment''' as well as '''uncomment''' a line. | ||
| − | |- | + | |- |
|| Highlight '''hash '''symbol | || Highlight '''hash '''symbol | ||
|| On doing so, we see a '''hash '''symbol with space. | || On doing so, we see a '''hash '''symbol with space. | ||
| − | |- | + | |- |
|| Delete''' # symbol''' | || Delete''' # symbol''' | ||
|| For now, we will '''uncomment print(secondVar)''' and save our '''script'''. | || For now, we will '''uncomment print(secondVar)''' and save our '''script'''. | ||
| − | Delete ''' | + | Delete '''# hash''' symbol at the beginning of this line. |
| − | + | |- | |
| − | |- | + | |
|| [RStudio] | || [RStudio] | ||
Click on the '''Source''' button | Click on the '''Source''' button | ||
| − | || Now let’s run the '''script''' file. | + | || Now let’s '''run''' the '''script''' file. |
| − | + | ||
In the top right corner of the '''Source''' window, click on the '''Source '''button. | In the top right corner of the '''Source''' window, click on the '''Source '''button. | ||
| − | |- | + | |- |
| + | || | ||
| + | || Now maximize the '''Console'''. | ||
| + | |- | ||
|| Highlight the '''Console '''window | || Highlight the '''Console '''window | ||
| − | || | + | || The line-by-line execution of the '''script '''is shown in the '''Console '''window. |
| − | |- | + | |- |
|| Highlight the output in '''Console''' | || Highlight the output in '''Console''' | ||
|| The '''sample vector [1 2 3 4] '''is printed. | || The '''sample vector [1 2 3 4] '''is printed. | ||
| − | |||
The values of two '''variables,''' 10 and 15 are printed. | The values of two '''variables,''' 10 and 15 are printed. | ||
| − | |- | + | |- |
| − | || | + | || Click on the broom icon in the '''Console '''window |
|| We will clear the '''Console''' by clicking on the broom icon. | || We will clear the '''Console''' by clicking on the broom icon. | ||
| − | |- | + | |- |
| + | || | ||
| + | || Now, we minimize the '''Console '''window. | ||
| + | |- | ||
|| | || | ||
|| Now let’s move ahead. | || Now let’s move ahead. | ||
| − | |- | + | |- |
|| Highlight the file '''myfirstscript.R''' | || Highlight the file '''myfirstscript.R''' | ||
|| Suppose, we want to run only a '''block of code '''after '''print(testSample) '''from the file '''myfirstscript.R. ''' | || Suppose, we want to run only a '''block of code '''after '''print(testSample) '''from the file '''myfirstscript.R. ''' | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
Highlighting the block of code | Highlighting the block of code | ||
|| First, select or highlight the''' block of code''', starting from '''firstVar''' '''equals 10 '''to the end. | || First, select or highlight the''' block of code''', starting from '''firstVar''' '''equals 10 '''to the end. | ||
| − | |- | + | |- |
|| Click on''' Run''' button | || Click on''' Run''' button | ||
|| Then in the top right corner of the '''Source '''window, click on the '''Run '''button with an arrow. | || Then in the top right corner of the '''Source '''window, click on the '''Run '''button with an arrow. | ||
| − | |- | + | |- |
|| Highlight the output in '''Console '''window | || Highlight the output in '''Console '''window | ||
|| Now you can see the output of only the highlighted part of the code in the '''Console''' window. | || Now you can see the output of only the highlighted part of the code in the '''Console''' window. | ||
| − | |||
The output shows the values of two '''variables, '''10 and 15 only. | The output shows the values of two '''variables, '''10 and 15 only. | ||
| − | |- | + | |- |
|| Run a block using '''Ctrl+Enter''' | || Run a block using '''Ctrl+Enter''' | ||
|| You can also run a particular '''block''' by highlighting it and pressing '''Ctrl+Enter''' together. | || You can also run a particular '''block''' by highlighting it and pressing '''Ctrl+Enter''' together. | ||
| − | |- | + | |- |
|| Click on broom icon | || Click on broom icon | ||
|| We will clear the '''Console''' window by clicking on the broom icon. | || We will clear the '''Console''' window by clicking on the broom icon. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
Creating an R script using '''Ctrl+Shift+N''' | Creating an R script using '''Ctrl+Shift+N''' | ||
| − | || Now | + | || Now let us create another '''R script'''. |
Use '''Ctrl+Shift+N''' to open a new '''script'''. | Use '''Ctrl+Shift+N''' to open a new '''script'''. | ||
Save this '''script''' in the same folder '''myProject''' with the name '''mysecondscript.''' | Save this '''script''' in the same folder '''myProject''' with the name '''mysecondscript.''' | ||
| − | |- | + | |- |
|| | || | ||
|| Now let’s learn how to load''' myfirstscript.R''' into '''mysecondscript.R'''. | || Now let’s learn how to load''' myfirstscript.R''' into '''mysecondscript.R'''. | ||
| − | |- | + | |- |
|| [RStudio] | || [RStudio] | ||
'''Source''' | '''Source''' | ||
|| Go to''' myfirstscript.R '''and run it by clicking on the '''Source''' button. | || Go to''' myfirstscript.R '''and run it by clicking on the '''Source''' button. | ||
| − | |- | + | |- |
|| Highlight the '''source '''line | || Highlight the '''source '''line | ||
'''source('~/Desktop/myProject/myfirstscript.R', echo=TRUE)'''. | '''source('~/Desktop/myProject/myfirstscript.R', echo=TRUE)'''. | ||
| − | || In the '''Console''' window, scroll up to locate the '''source''' for this '''script'''. | + | || In the '''Console''' window, scroll up to locate the '''source''' for this '''script'''. |
| − | |- | + | |- |
|| Copying the '''source '''line | || Copying the '''source '''line | ||
| − | || Copy it without the ''' | + | || Copy it without the '''symbol. ''' |
| − | |- | + | |- |
|| Back to '''mysecondscript.R''' | || Back to '''mysecondscript.R''' | ||
| − | || Now let’s get back to our new '''script | + | || Now let’s get back to our new '''script mysecondscript.R''' |
| − | |- | + | |- |
|| Pasting the '''source '''line | || Pasting the '''source '''line | ||
|| Paste what we have just copied, at the top of the''' script mysecondscript.R ''' | || Paste what we have just copied, at the top of the''' script mysecondscript.R ''' | ||
| − | |- | + | |- |
|| | || | ||
|| We can press '''Enter''' after comma for better visibility. | || We can press '''Enter''' after comma for better visibility. | ||
| − | |- | + | |- |
|| Type '''print("Script loaded")''' | || Type '''print("Script loaded")''' | ||
|| Next, write one more line to ensure that the execution is from this '''script''' only. | || Next, write one more line to ensure that the execution is from this '''script''' only. | ||
| − | |||
In the '''Source''' window, type '''print '''and then the following words in''' parentheses.''' | In the '''Source''' window, type '''print '''and then the following words in''' parentheses.''' | ||
In double quotes''', Script space loaded.''' | In double quotes''', Script space loaded.''' | ||
| − | |||
Press''' Enter. ''' | Press''' Enter. ''' | ||
| − | |- | + | |- |
|| Press '''Ctrl+S''' keys | || Press '''Ctrl+S''' keys | ||
|| Save the '''script.''' | || Save the '''script.''' | ||
| − | |- | + | |- |
|| Click on the broom icon in '''Console''' | || Click on the broom icon in '''Console''' | ||
| − | || Let us clear the Console again by clicking on the broom icon. | + | || Let us clear the '''Console '''again by clicking on the broom icon. |
| − | |- | + | |- |
|| Press '''Ctrl+Shift+Enter''' keys | || Press '''Ctrl+Shift+Enter''' keys | ||
| − | || Now run the '''script''' by pressing | + | || Now run the '''script''' by pressing '''Ctrl+Shift+Enter''' together. |
| − | |- | + | |- |
| + | || | ||
| + | || Maximize the '''Console '''window. | ||
| + | |- | ||
|| Highlight the output | || Highlight the output | ||
| − | || | + | || You can see the output in the '''Console''' window and verify the results. |
| − | |- | + | |- |
| + | || | ||
| + | || Now, we minimize the '''Console ''' window. | ||
| + | |- | ||
|| | || | ||
|| This brings us to the end of this tutorial. Let us summarize. | || This brings us to the end of this tutorial. Let us summarize. | ||
| − | |- | + | |- |
|| Show slide | || Show slide | ||
Summary | Summary | ||
| − | || | + | || We have learned |
| + | * How to create, save and run an '''R script''' | ||
| − | + | |- | |
| − | |- | + | |
|| Show slide | || Show slide | ||
Assignment | Assignment | ||
| − | || We now suggest an assignment.* | + | || We now suggest an assignment. |
| − | * | + | * Create a '''script''' and save it on '''Desktop''' as '''testscript.R ''' |
| + | * Load '''myfirstscript.R''' in this '''script '''and run it. | ||
| − | + | |- | |
| − | |- | + | |
|| Show slide | || Show slide | ||
About the Spoken Tutorial Project | About the Spoken Tutorial Project | ||
|| The video at the following link summarises the Spoken Tutorial project. | || The video at the following link summarises the Spoken Tutorial project. | ||
| − | |||
Please download and watch it. | Please download and watch it. | ||
| − | |- | + | |- |
|| Show slide | || Show slide | ||
| Line 392: | Line 378: | ||
Please contact us. | Please contact us. | ||
| − | |- | + | |- |
|| Show Slide | || Show Slide | ||
Forum to answer questions | Forum to answer questions | ||
| − | || | + | || Do you have questions in THIS '''Spoken Tutorial?''' |
Choose the minute and second where you have the question. | Choose the minute and second where you have the question. | ||
| Line 405: | Line 391: | ||
Please visit this site. | Please visit this site. | ||
| − | |- | + | |- |
| − | || | + | || Show Slide |
| − | + | ||
| − | Show Slide | + | |
Forum to answer questions | Forum to answer questions | ||
| Line 414: | Line 398: | ||
Please visit the forum given in the link. | Please visit the forum given in the link. | ||
| − | |- | + | |- |
|| Show Slide | || Show Slide | ||
Textbook Companion | Textbook Companion | ||
| − | || | + | || The '''FOSSEE ''' team coordinates coding of solved examples of popular books. |
| − | We give honorarium and certificates | + | We give honorarium and certificates to those who do this. |
For more details, please visit these sites. | For more details, please visit these sites. | ||
| − | |- | + | |- |
|| Show Slide | || Show Slide | ||
Acknowledgement | Acknowledgement | ||
|| The Spoken Tutorial project is funded by NMEICT, MHRD, Govt. of India | || The Spoken Tutorial project is funded by NMEICT, MHRD, Govt. of India | ||
| − | |- | + | |- |
|| Show Slide | || Show Slide | ||
Thank You | Thank You | ||
| − | || | + | || The script for this tutorial was contributed by Shaik Sameer (FOSSEE Fellow 2018). |
| − | + | ||
| − | + | ||
| − | + | ||
This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching. | This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching. | ||
|- | |- | ||
|} | |} | ||
| − | |||
Latest revision as of 17:52, 9 October 2019
Title of script: Introduction to R script
Authors: Shaik Sameer (IIIT Vadodara) and Sudhakar Kumar (IIT Bombay)
Keywords: R, RStudio, script, video tutorial
| Visual Cue | Narration |
| Show slide
Opening slide |
Welcome to this tutorial on Introduction to R script. |
| Show slide
Objectives |
In this tutorial, you will learn:
|
| Show slide
Pre-requisites |
To understand this tutorial, you should know basic commands of R.
If not, please locate the relevant tutorials on R on this website. |
| Show slide
Systems requirements |
This tutorial is recorded on
Install R version 3.2.0 or higher. |
| Show slide
What is R script |
|
| Show slide
Creating a folder for our project |
|
| [RStudio]
RStudio window |
Let us switch to RStudio. |
| [RStudio]
Highlight the tabs Untitled1 and R packages available in the Source window |
We will close these two tabs named Untitled1 and R packages available.
Click on the small cross symbol next to these tabs. |
| [RStudio]
Click on the green plus sign >> select R Script from the dropdown |
We will now create a new R script.
|
| Highlight the new R script Untitled1 | A new R script appears in the Source window.
You can also create a new R script by pressing Ctrl+Shift+N together. |
| Click on File | Let us save this R script first.
In the top left corner of the screen, click on the File option. |
| Click on Save option | Then click on Save to save the script. |
| Select the directory myProject>> type name myfirstscript>> click on Save button | Select the directory where you want to save your R script.
I am saving the script in the folder myProject on my Desktop, with the name myfirstscript. Finally, click on the Save button. |
| Point to myfirstscript.R in the Source window | Now you can see that the file is named as myfirstscript.R.
RStudio automatically adds dot R at the end of the filename. |
| Now, let us write some lines of code in the script file myfirstscript.R. | |
| [RStudio]
testSample <- c(1,2,3,4) |
We will create a vector named testSample with one two three four as its elements.
We have already learned how to create vectors earlier in this series. In the Source window, type testSample space less than symbol.Now type hyphen space c 1 comma 2 comma 3 comma 4 in parentheses. Press Enter. |
| Highlight <- symbol | You may also use equal sign in place of less than symbol followed by hyphen. |
| Highlight Save icon | In the Source window, to the left of the checkbox Source on Save, click on the Save icon.
Or, press Ctrl+S together to save the file. |
| [RStudio]
print(testSample) |
We will now use the print function to display the values in testSample vector.
In the Source window, type p r i |
| Highlight the predicted functions | RStudio automatically starts suggesting different functions. |
| You can navigate this list of functions by using the up (↑) and down (↓) arrow keys on the keyboard. | |
| Press Enter | To select a particular function, just press Enter. |
| Finish typing print testSample in parentheses and press Enter. | |
| Press Ctrl+S | Now let’s save the file and run it with these two lines only. |
| Now, we maximize the Source window. | |
| [RStudio]
Highlight Source button in the Source window Highlight the output in Console window |
In the top right corner of the Source window, click on the Source button.
You can see the line-by-line execution of the script in the Console. You can also run the script by pressing Ctrl+Shift+Enter together. For this, you need to first click in the script window. |
| [RStudio]
firstVar = 10 |
Now let’s declare a variable firstVar with value of ten in the Source window.
Type firstVar with capital V space equal sign space 10 and press Enter. |
| Please note that R language is case-sensitive. | |
| [RStudio]
print(firstVar) |
We will now use the print function to show the value of firstVar.
In the Source window, type print. I am typing only p r i n but the options appear and I select print from there. Now in parentheses, start typing firstVar. RStudio shows firstVar; press Enter to select it. Press Enter to go to the next line. |
| [RStudio]
secondVar = 15 print(secondVar) |
Now let’s declare another variable secondVar with value of fifteen.
In the Source window, type secondVar space equal sign space 15 and press Enter. Now, as shown before, type print secondVar in parentheses to show its value and press Enter . |
| We can add comments to our code by using # hash symbol followed by our comment. | |
| [RStudio]
# Creating an R script Highlight the comment line and first line of code |
Type hash symbol space Creating an R script before the declaration of testSample vector.
R interprets each line of code. Please make sure that your comment and the first line of code appear in separate lines. |
| Click on the line print(secondVar) | Now, let’s comment the line print(secondVar).
To do that, first click on this line. |
| from Code option >>
Comment/Uncomment Lines |
Then from the top menu bar of RStudio, click on the Code option.
From the dropdown menu, click on the Comment/Uncomment Lines option. This option helps us to comment as well as uncomment a line. |
| Highlight hash symbol | On doing so, we see a hash symbol with space. |
| Delete # symbol | For now, we will uncomment print(secondVar) and save our script.
Delete # hash symbol at the beginning of this line. |
| [RStudio]
Click on the Source button |
Now let’s run the script file.
In the top right corner of the Source window, click on the Source button. |
| Now maximize the Console. | |
| Highlight the Console window | The line-by-line execution of the script is shown in the Console window. |
| Highlight the output in Console | The sample vector [1 2 3 4] is printed.
The values of two variables, 10 and 15 are printed. |
| Click on the broom icon in the Console window | We will clear the Console by clicking on the broom icon. |
| Now, we minimize the Console window. | |
| Now let’s move ahead. | |
| Highlight the file myfirstscript.R | Suppose, we want to run only a block of code after print(testSample) from the file myfirstscript.R. |
| [RStudio]
Highlighting the block of code |
First, select or highlight the block of code, starting from firstVar equals 10 to the end. |
| Click on Run button | Then in the top right corner of the Source window, click on the Run button with an arrow. |
| Highlight the output in Console window | Now you can see the output of only the highlighted part of the code in the Console window.
The output shows the values of two variables, 10 and 15 only. |
| Run a block using Ctrl+Enter | You can also run a particular block by highlighting it and pressing Ctrl+Enter together. |
| Click on broom icon | We will clear the Console window by clicking on the broom icon. |
| [RStudio]
Creating an R script using Ctrl+Shift+N |
Now let us create another R script.
Use Ctrl+Shift+N to open a new script. Save this script in the same folder myProject with the name mysecondscript. |
| Now let’s learn how to load myfirstscript.R into mysecondscript.R. | |
| [RStudio]
Source |
Go to myfirstscript.R and run it by clicking on the Source button. |
| Highlight the source line
source('~/Desktop/myProject/myfirstscript.R', echo=TRUE). |
In the Console window, scroll up to locate the source for this script. |
| Copying the source line | Copy it without the symbol. |
| Back to mysecondscript.R | Now let’s get back to our new script mysecondscript.R |
| Pasting the source line | Paste what we have just copied, at the top of the script mysecondscript.R |
| We can press Enter after comma for better visibility. | |
| Type print("Script loaded") | Next, write one more line to ensure that the execution is from this script only.
In the Source window, type print and then the following words in parentheses. In double quotes, Script space loaded. Press Enter. |
| Press Ctrl+S keys | Save the script. |
| Click on the broom icon in Console | Let us clear the Console again by clicking on the broom icon. |
| Press Ctrl+Shift+Enter keys | Now run the script by pressing Ctrl+Shift+Enter together. |
| Maximize the Console window. | |
| Highlight the output | You can see the output in the Console window and verify the results. |
| Now, we minimize the Console window. | |
| This brings us to the end of this tutorial. Let us summarize. | |
| Show slide
Summary |
We have learned
|
| Show slide
Assignment |
We now suggest an assignment.
|
| Show slide
About the Spoken Tutorial Project |
The video at the following link summarises the Spoken Tutorial project.
Please download and watch it. |
| Show slide
Spoken Tutorial Workshops |
We conduct workshops using Spoken Tutorials and give certificates.
Please contact us. |
| Show Slide
Forum to answer questions |
Do you have questions in THIS Spoken Tutorial?
Choose the minute and second where you have the question. Explain your question briefly. Someone from the FOSSEE team will answer them. Please visit this site. |
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Forum to answer questions |
Do you have any general / technical questions?
Please visit the forum given in the link. |
| Show Slide
Textbook Companion |
The FOSSEE team coordinates coding of solved examples of popular books.
We give honorarium and certificates to those who do this. For more details, please visit these sites. |
| Show Slide
Acknowledgement |
The Spoken Tutorial project is funded by NMEICT, MHRD, Govt. of India |
| Show Slide
Thank You |
The script for this tutorial was contributed by Shaik Sameer (FOSSEE Fellow 2018).
This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching. |
