R/C2/Aesthetic-Mapping-in-ggplot2/English - Revision history

Nancyvarkey at 09:01, 23 September 2019

2019-09-23T09:01:19Z

Madhurig at 07:10, 1 August 2019

2019-08-01T07:10:02Z

Nancyvarkey at 02:02, 26 July 2019

2019-07-26T02:02:05Z

Sudhakarst at 11:07, 11 July 2019

2019-07-11T11:07:00Z

Sudhakarst at 11:06, 11 July 2019

2019-07-11T11:06:37Z

Sudhakarst at 11:05, 11 July 2019

2019-07-11T11:05:52Z

Sudhakarst at 11:05, 11 July 2019

2019-07-11T11:05:31Z

Sudhakarst: Created page with "'''Title of the script''': Aesthetic Mapping in ggplot2 '''Author''': Varshit Dubey (CoE Pune) and Sudhakar Kumar (IIT Bombay) '''Keywords''': R, RStudio, ggplot, aesthetic,..."

2019-07-11T11:04:35Z

Created page with "'''Title of the script''': Aesthetic Mapping in ggplot2 '''Author''': Varshit Dubey (CoE Pune) and Sudhakar Kumar (IIT Bombay) '''Keywords''': R, RStudio, ggplot, aesthetic,..."

New page

'''Title of the script''': Aesthetic Mapping in ggplot2

'''Author''': Varshit Dubey (CoE Pune) and Sudhakar Kumar (IIT Bombay)

'''Keywords''': R, RStudio, ggplot, aesthetic, mapping, video tutorial, spoken tutorial

{| border =1
|'''Visual Cue’’’
|'''Narration’’’
|-
|| Show slide

Opening Slide
|| Welcome to this tutorial on '''Aesthetic Mapping in ggplot2'''.
|-
|| Show slide

Learning Objective
|| In this tutorial, we will learn,
* What is''' aesthetic'''
* How to create plots using '''aesthetic'''
* Tuning parameters in '''aesthetic'''

|-
||

Show slide

Pre-requisites
|| To understand this tutorial, you should know,
* Basics of statistics
* Basics of '''ggplot2''' package
* Data frames

If not, please locate the relevant tutorials on '''R''' on this website.
|-
|| Show slide

System Specifications
|| This tutorial is recorded on
* '''Ubuntu Linux '''OS version '''16.04'''
* '''R''' version '''3.4.4'''
* '''RStudio''' version '''1.1.463'''

Install '''R''' version '''3.2.0''' or higher.
|-
|| Show slide

Download Files
|| For this tutorial, we will use* A '''data frame''' '''moviesData.csv''', and
* A '''script''' file '''aesPlots.R'''.

Please download these files from the '''Code files''' link of this tutorial.
|-
|| [Computer screen]

Highlight '''moviesData.csv '''and''' aesPlots.R '''in the folder '''aesPlots '''

Point to''' aesPlots folder.'''
|| I have downloaded and moved these files to '''aesPlots''' folder.

This folder is located in '''myProject''' folder on my '''Desktop'''.

I have set '''aesPlots''' folder as my '''Working Directory.'''
|-
||
|| Now let us see what is '''Aesthetic?'''
|-
|| Show slide

What is Aesthetics
|| * '''Aesthetic '''is a visual property of the objects in a plot.
* It includes lines, points, symbols, colors, and position.
* It is used to add '''customization '''to our plots.

|-
||
|| Let us switch to '''RStudio'''.
|-
|| Highlight '''aesPlots.R''' in the '''Files '''window''' '''of '''RStudio '''
|| Open the '''script aesPlots.R '''in''' RStudio'''.
|-
|| Highlight '''ggplot''' function in the '''Source''' window
|| Here, we are plotting a '''scatter plot''' between '''critics_score''' and '''audience_score''' of '''movies'''.
|-
|| Highlight the '''Source''' button
|| Run this '''script''' by clicking on the '''Source button'''.
|-
|| Highlight '''Plots''' window
|| '''Scatter plot''' appears in the '''Plots''' window.
|-
|| Highlight '''movies''' in the '''Source''' window
|| '''movies '''data frame opens in the '''Source''' window.
|-
|| Highlight the plot in the '''Plots''' window
|| In this '''scatter plot''', each point refers to a particular movie.

Suppose we want to color these points according to the '''genre''' of the movies.
|-
|| Highlight the scroll bar in the '''Source''' window
|| In the '''Source''' window, scroll from left to right.
|-
|| Highlight '''genre''' in the '''Source''' window
|| As we can see that there are different genres like
* '''Drama'''
* '''Comedy'''
* '''Horror'''
* '''Documentary''', etc.

So, we will assign a unique color to each genre.
|-
|| Highlight the '''script aesPlots.R''' in the '''Source''' window
|| Click on the '''script aesPlots.R'''
|-
| | '''[RStudio]'''

'''ggplot(data = movies, '''

'''mapping = aes(x = critics_score,'''

'''y = audience_score, '''

'''color = genre)) +'''

'''geom_point()'''
| | In the '''Source''' window, type the following commands.
|-
| | Highlight '''aes''' in the '''Source''' window
| | Inside '''aes''', we have added '''color''' argument and set it to '''genre'''.
|-
|| Highlight '''run''' button in the '''Source''' window
|| Save the '''script''' and run the current line by pressing '''Ctrl+Enter''' keys simultaneosuly.
|-
|| Highlight '''Plots''' window
|| Modified''' scatter plot''' appears in the '''Plots''' window.
|-
|| Click on '''Zoom''' button to maximize the plot.

Highlight '''Plots''' window
|| In the '''Plots''' window, click on the '''Zoom''' button to maximize the plot.
|-
|| Highlight the plot
|| We can see that each point is assigned a unique '''color''' according to its '''genre'''.

In the right side of the plot, we can view the mapping of '''genres''' with their colors.
|-
|| Click on X button to close the plot.
|| Close this plot.
|-
|| Highlight '''ggplot''' in the '''Source''' window
|| Now, we will learn how to draw a '''bar chart''' using '''ggplot '''function.
|-
|| Highlight '''movies''' in the '''Source''' window
|| In the '''Source''' window, click on '''movies'''.
|-
|| Highlight the scroll bar in the '''Source''' window
|| In the '''Source''' window, scroll from left to right.
|-
|| Highlight '''mpaa_rating''' in the '''Source''' window
|| Let us inspect the object named '''mpaa '''underscore '''rating''' in '''movies'''.
|-
|| Highlight the '''script aesPlots.R''' in the '''Source''' window
|| Click on the '''script aesPlots.R'''
|-
|| '''[RStudio]'''

'''str(movies$mpaa_rating)'''

'''levels(movies$mpaa_rating)'''
|| In the '''Source''' window, type the following commands.
|-
|| Highlight '''run''' button in the '''Source''' window
|| Run the last two lines of code.
|-
|| Highlight output in the '''Console''' window
|| '''mpaa_rating '''is a '''factor'''.

It has 6''' '''levels like
* '''G'''
* '''NC-17'''
* '''PG'''
* '''PG-13'''
* '''R''', and
* '''Unrated'''.

|-
|| Highlight output in the '''Console''' window
|| So, our '''bar chart''' will have 6 different bars.

Each bar will represent the number of movies in each level.
|-
|| '''[RStudio]'''

'''ggplot(data = movies, '''

'''mapping = aes(x = mpaa_rating)) + '''

'''geom_bar()'''
|| In the '''Source''' window, type the following command.
|-
|| Highlight '''aes''' in the '''Source''' window
|| Here, we have mapped '''mpaa '''underscore '''rating''' on X-axis.
|-
|| Highlight '''geom_bar''' in the Source window
|| Next, we have used '''geom '''underscore '''bar''' as we are plotting a '''bar chart'''.

Similarly, we can use
* '''geom_line''' to draw a line chart
* '''geom_boxplot''' to draw a box plot

|-
|| Highlight '''run''' button in the '''Source''' window
|| Run the current line.
|-
|| Highlight '''Plots''' window
|| The '''bar chart''' appears in the '''Plots''' window.
|-
|| Highlight plot in the '''Plots''' window
|| Now, we will learn how to add labels to this '''bar chart'''.
|-
|| Point to''' geom_bar().'''

Type''' Space '''plus sign >> press Enter.
|| In the '''Source''' window, after '''geom_bar(), '''type space plus sign and press '''Enter'''.
|-
|| '''[RStudio]'''

'''labs(y = "Rating count",'''

'''title = "Count of mpaa_rating")'''
||

Now type the following command.
|-
|| Highlight labs in the Source window
|| Here, we have used '''labs''' argument to add label and title to the bar chart.
|-
|| Highlight '''run''' button in the '''Source''' window
|| Run the current line.
|-
|| Highlight '''Plots''' window
|| The modified '''bar chart''' appears in the '''Plots''' window.
|-
|| Highlight fifth bar in the '''Plots''' window
|| We can see that most of the movies have been rated as '''R''' in '''mpaa_rating'''.

Suppose, in this bar chart, we want to view the distribution of movies by '''genre'''.
|-
|| [RStudio]

'''ggplot(data = movies, '''

'''mapping = aes(x = mpaa_rating, fill = genre)) + '''

'''geom_bar() +'''

'''labs(y = "Rating count",'''

'''title = "Count of mpaa_rating by genre")'''
|| In the '''Source''' window, type the following command.
|-
|| Highlight '''fill''' in the '''Source''' window
|| Inside '''aes''', we have added '''fill''' argument and set it to '''genre'''.
|-
|| Highlight '''run''' button in the '''Source''' window
|| Run the current line.
|-
|| Highlight '''Plots''' window
|| The modified '''bar chart''' appears in the '''Plots''' window.
|-
|| Highlight '''Plots''' window
|| In the '''Plots''' window, click on the '''Zoom''' button to maximize the plot.
|-
|| Highlight fifth bar in the '''Plots''' window
|| There are seven different colors in each bar. Besides the plot, the meaning of each color has been given
|-
|| Click on X button to close the plot.
|| Close the plot.
|-
|| Highlight '''movies''' in the '''Source''' window
|| In the '''Source''' window, click on '''movies data frame'''.
|-
|| Highlight '''runtime '''in the '''Source''' window
|| Now we will plot a '''histogram '''for''' '''the '''object''' named as '''runtime '''in '''movies'''.

Recall that, we have already learned how to plot a histogram using '''hist''' function.

Now we will use '''ggplot2 '''package to plot a '''histogram'''.
|-
|| Highlight the '''script aesPlots.R''' in the '''Source''' window.
|| Click on the '''script aesPlots.R'''
|-
|| [RStudio]

'''ggplot(data = movies,'''

'''mapping = aes(x = runtime)) +'''

'''geom_histogram() + '''

'''labs(x = "Runtime of movies",'''

'''title = "Distribution of movies' runtime")'''
|| In the '''Source''' window, type the following command.
|-
|| Highlight '''run''' button in the '''Source''' window
|| Save the '''script''' and run the current line.
|-
|| Highlight output in the '''Console''' window
|| There are some warning messages, which we will ignore for now.
|-
|| Highlight '''Plots''' window
|| The histogram appears in the '''Plots''' window.
|-
||
|| Let us summarize what we have learnt.
|-
|| Show slide

Summary
|| In this tutorial, we have learnt,
* What is''' aesthetic'''
* How to create plots using '''aesthetic'''
* Tuning parameters in '''aesthetic'''

|-
|| Show slide

Assignment

|| We now suggest an assignment.
* Using built-in data set '''mtcars, '''draw a bar chart from the object '''cyl'''.
* Add suitable labels to this bar chart.

|-
|| 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
|| Please post your timed queries in this forum.
|-
|| Show Slide

Forum to answer questions
|| Please post your general queries in this forum.
|-
|| Show Slide

Textbook Companion
|| The '''FOSSEE '''team coordinates the '''TBC '''project.

For more details, please visit these sites.
|-
|| Show Slide

Acknowledgment
|| The Spoken Tutorial project is funded by NMEICT, MHRD, Govt. of India
|-
|| Show Slide

Thank You
|| The script for this tutorial was contributed by Varshit Dubey (CoE Pune).

This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching.
|-
|}

← Older revision		Revision as of 11:07, 11 July 2019
Line 4:		Line 4:

	'''Keywords''': R, RStudio, ggplot, aesthetic, mapping, video tutorial, spoken tutorial		'''Keywords''': R, RStudio, ggplot, aesthetic, mapping, video tutorial, spoken tutorial
−

	{\| border =1		{\| border =1

@@ Line 102: / Line 102: @@
 |-
 || Highlight '''genre''' in the '''Source''' window
-|| As we can see that there are different genres like
+|| As we can see that there are different '''genres''' like
 * '''Drama'''
 * '''Comedy'''
@@ Line 108: / Line 108: @@
 * '''Documentary''', etc.
-So, we will assign a unique color to each genre.
+So, we will assign a unique color to each '''genre'''.
 |-
 || Highlight the '''script aesPlots.R''' in the '''Source''' window

@@ Line 3: / Line 3: @@
 '''Author''': Varshit Dubey (CoE Pune) and Sudhakar Kumar (IIT Bombay)
-'''Keywords''': R, RStudio, ggplot, aesthetic, mapping, video tutorial, spoken tutorial
+'''Keywords''': R, RStudio, ggplot, aesthetic, mapping, video tutorial.
 {| border =1
@@ Line 23: / Line 23: @@
 |-
-||
+|| Show slide
-−
 Show slide
 Pre-requisites
@@ Line 49: / Line 47: @@
 Download Files
 || For this tutorial, we will use
-* A '''data frame''' '''moviesData.csv''', and
+* A '''data frame moviesData.csv''', and
 * A '''script''' file '''aesPlots.R'''.
@@ Line 66: / Line 64: @@
 |-
 ||
-|| Now let us see what is '''Aesthetic?'''
+|| Now let us see what is '''Aesthetic'''?
 |-
 || Show slide
@@ Line 74: / Line 72: @@
 * '''Aesthetic '''is a visual property of the objects in a plot.
 * It includes lines, points, symbols, colors, and position.
-* It is used to add '''customization '''to our plots.
+* It is used to add '''customization''' to our plots.
 |-
-||
+|| Cursor on the interface.
 || Let us switch to '''RStudio'''.
 |-
 || Highlight '''aesPlots.R''' in the '''Files '''window''' '''of '''RStudio '''
-|| Open the '''script aesPlots.R '''in''' RStudio'''.
+|| Open the '''script aesPlots.R''' in '''RStudio'''.
 |-
 || Highlight '''ggplot''' function in the '''Source''' window
@@ Line 115: / Line 113: @@
 || Click on the '''script aesPlots.R'''
 |-
-|  | '''[RStudio]'''
+|| '''[RStudio]'''
 '''ggplot(data = movies, '''
@@ Line 126: / Line 124: @@
 '''geom_point()'''
-|  | In the '''Source''' window, type the following '''commands'''.
+||In the '''Source''' window, type the following '''commands'''.
 |-
-|  | Highlight '''aes''' in the '''Source''' window
+||Highlight '''aes''' in the '''Source''' window
-|  | Inside '''aes''', we have added '''color argument''' and set it to '''genre'''.
+||Inside '''aes''', we have added '''color argument''' and set it to '''genre'''.
 |-
 || Highlight '''run''' button in the '''Source''' window
-|| Save the '''script''' and run the current line by pressing '''Ctrl+Enter''' keys simultaneously.
+|| Save the '''script''' and run the current line by pressing '''Ctrl+ Enter''' keys simultaneously.
 |-
 || Highlight '''Plots''' window
@@ Line 196: / Line 194: @@
 || '''[RStudio]'''
-'''ggplot(data = movies, '''
+'''ggplot(data = movies''',
 '''mapping = aes(x = mpaa_rating)) + '''
@@ Line 233: / Line 231: @@
 '''title = "Count of mpaa_rating")'''
-||
+|| Now type the following '''commands'''.
-−
-Now type the following '''command'''.
 |-
 || Highlight labs in the Source window
@@ Line 289: / Line 285: @@
 |-
 || Highlight '''runtime '''in the '''Source''' window
-|| Now we will plot a '''histogram '''for the '''object''' named as '''runtime '''in '''movies'''.
+|| Now we will plot a '''histogram '''for the '''object''' named as '''runtime''' in '''movies'''.
@@ Line 329: / Line 325: @@
 Summary
 || In this tutorial, we have learnt,
-* What is''' aesthetic'''
+* What is '''aesthetic'''
 * How to create plots using '''aesthetic'''
 * Tuning parameters in '''aesthetic'''
@@ Line 339: / Line 335: @@
 || We now suggest an assignment.
-* Using '''built-in data set mtcars, '''draw a bar chart from the '''object cyl'''.
+* Using '''built-in data set mtcars''', draw a bar chart from the '''object cyl'''.
 * Add suitable labels to this bar chart.

@@ Line 93: / Line 93: @@
 |-
 || Highlight '''movies''' in the '''Source''' window
-|| '''movies '''data frame opens in the '''Source''' window.
+|| '''movies data frame''' opens in the '''Source''' window.
 |-
 || Highlight the plot in the '''Plots''' window
@@ Line 126: / Line 126: @@
 '''geom_point()'''
-|  | In the '''Source''' window, type the following commands.
+|  | In the '''Source''' window, type the following '''commands'''.
 |-
 |  | Highlight '''aes''' in the '''Source''' window
-|  | Inside '''aes''', we have added '''color''' argument and set it to '''genre'''.
+|  | Inside '''aes''', we have added '''color argument''' and set it to '''genre'''.
 |-
 || Highlight '''run''' button in the '''Source''' window
-|| Save the '''script''' and run the current line by pressing '''Ctrl+Enter''' keys simultaneosuly.
+|| Save the '''script''' and run the current line by pressing '''Ctrl+Enter''' keys simultaneously.
 |-
 || Highlight '''Plots''' window
@@ Line 144: / Line 144: @@
 || Highlight the plot
 || We can see that each point is assigned a unique '''color''' according to its '''genre'''.
 In the right side of the plot, we can view the mapping of '''genres''' with their colors.
@@ Line 151: / Line 152: @@
 |-
 || Highlight '''ggplot''' in the '''Source''' window
-|| Now, we will learn how to draw a '''bar chart''' using '''ggplot '''function.
+|| Now, we will learn how to draw a '''bar chart''' using '''ggplot function'''.
 |-
 || Highlight '''movies''' in the '''Source''' window
@@ Line 160: / Line 161: @@
 |-
 || Highlight '''mpaa_rating''' in the '''Source''' window
-|| Let us inspect the object named '''mpaa '''underscore '''rating''' in '''movies'''.
+|| Let us inspect the '''object''' named '''mpaa underscore rating''' in '''movies'''.
 |-
 || Highlight the '''script aesPlots.R''' in the '''Source''' window
@@ Line 170: / Line 171: @@
 '''levels(movies$mpaa_rating)'''
-|| In the '''Source''' window, type the following commands.
+|| In the '''Source''' window, type the following '''commands'''.
 |-
 || Highlight '''run''' button in the '''Source''' window
@@ Line 178: / Line 179: @@
 || '''mpaa_rating '''is a '''factor'''.
-It has 6''' '''levels like
+It has 6 '''levels''' like
 * '''G'''
 * '''NC-17'''
@@ Line 190: / Line 191: @@
 || So, our '''bar chart''' will have 6 different bars.
 Each bar will represent the number of movies in each level.
 |-
 || '''[RStudio]'''
@@ Line 199: / Line 201: @@
 '''geom_bar()'''
-|| In the '''Source''' window, type the following command.
+|| In the '''Source''' window, type the following '''command'''.
 |-
 || Highlight '''aes''' in the '''Source''' window
-|| Here, we have mapped '''mpaa '''underscore '''rating''' on X-axis.
+|| Here, we have mapped '''mpaa underscore rating''' on X-axis.
 |-
 || Highlight '''geom_bar''' in the Source window
-|| Next, we have used '''geom '''underscore '''bar''' as we are plotting a '''bar chart'''.
+|| Next, we have used '''geom underscore bar''' as we are plotting a '''bar chart'''.
 Similarly, we can use
@@ Line 224: / Line 226: @@
 Type''' Space '''plus sign >> press Enter.
-|| In the '''Source''' window, after '''geom_bar(), '''type space plus sign and press '''Enter'''.
+|| In the '''Source''' window, after '''geom_bar(), '''type '''space plus sign''' and press '''Enter'''.
 |-
 || '''[RStudio]'''
@@ Line 233: / Line 235: @@
 ||
-Now type the following command.
+Now type the following '''command'''.
 |-
 || Highlight labs in the Source window
-|| Here, we have used '''labs''' argument to add label and title to the bar chart.
+|| Here, we have used '''labs argument''' to add label and title to the bar chart.
 |-
 || Highlight '''run''' button in the '''Source''' window
@@ Line 260: / Line 262: @@
 '''title = "Count of mpaa_rating by genre")'''
-|| In the '''Source''' window, type the following command.
+|| In the '''Source''' window, type the following '''command'''.
 |-
 || Highlight '''fill''' in the '''Source''' window
-|| Inside '''aes''', we have added '''fill''' argument and set it to '''genre'''.
+|| Inside '''aes''', we have added '''fill argument''' and set it to '''genre'''.
 |-
 || Highlight '''run''' button in the '''Source''' window
@@ Line 275: / Line 277: @@
 |-
 || Highlight fifth bar in the '''Plots''' window
-|| There are seven different colors in each bar. Besides the plot, the meaning of each color has been given
+|| There are seven different colors in each bar.
 |-
 || Click on X button to close the plot.
@@ Line 284: / Line 289: @@
 |-
 || Highlight '''runtime '''in the '''Source''' window
-|| Now we will plot a '''histogram '''for''' '''the '''object''' named as '''runtime '''in '''movies'''.
+|| Now we will plot a '''histogram '''for the '''object''' named as '''runtime '''in '''movies'''.
-Now we will use '''ggplot2 '''package to plot a '''histogram'''.
+Now we will use '''ggplot2 package''' to plot a '''histogram'''.
 |-
 || Highlight the '''script aesPlots.R''' in the '''Source''' window.
@@ Line 304: / Line 311: @@
 '''title = "Distribution of movies' runtime")'''
-|| In the '''Source''' window, type the following command.
+|| In the '''Source''' window, type the following '''command'''.
 |-
 || Highlight '''run''' button in the '''Source''' window
@@ Line 332: / Line 339: @@
 || We now suggest an assignment.
-* Using built-in data set '''mtcars, '''draw a bar chart from the object '''cyl'''.
+* Using '''built-in data set mtcars, '''draw a bar chart from the '''object cyl'''.
 * Add suitable labels to this bar chart.

@@ Line 190: / Line 190: @@
 || Highlight output in the '''Console''' window
 || So, our '''bar chart''' will have 6 different bars.
 Each bar will represent the number of movies in each level.
@@ Line 208: / Line 207: @@
 || Highlight '''geom_bar''' in the Source window
 || Next, we have used '''geom '''underscore '''bar''' as we are plotting a '''bar chart'''.
 Similarly, we can use
@@ Line 380: / Line 378: @@
 Thank You
 || The script for this tutorial was contributed by Varshit Dubey (CoE Pune).
 This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching.
 |-
 |}

@@ Line 7: / Line 7: @@
 {| border =1
-|'''Visual Cue’’’
+|'''Visual Cue'''
-|'''Narration’’’
+|'''Narration'''
 |-
 || Show slide
@@ Line 25: / Line 25: @@
 |-
 ||
 Show slide
@@ Line 45: / Line 43: @@
 * '''R''' version '''3.4.4'''
 * '''RStudio''' version '''1.1.463'''
 Install '''R''' version '''3.2.0''' or higher.
@@ Line 55: / Line 51: @@
 || For this tutorial, we will use* A '''data frame''' '''moviesData.csv''', and
 * A '''script''' file '''aesPlots.R'''.
 Please download these files from the '''Code files''' link of this tutorial.
@@ Line 63: / Line 57: @@
 Highlight '''moviesData.csv '''and''' aesPlots.R '''in the folder '''aesPlots '''
 Point to''' aesPlots folder.'''
 || I have downloaded and moved these files to '''aesPlots''' folder.
 This folder is located in '''myProject''' folder on my '''Desktop'''.
 I have set '''aesPlots''' folder as my '''Working Directory.'''
@@ Line 83: / Line 74: @@
 * It includes lines, points, symbols, colors, and position.
 * It is used to add '''customization '''to our plots.
 |-
@@ Line 118: / Line 108: @@
 * '''Horror'''
 * '''Documentary''', etc.
 So, we will assign a unique color to each genre.
@@ Line 196: / Line 184: @@
 * '''R''', and
 * '''Unrated'''.
 |-
@@ Line 224: / Line 211: @@
 * '''geom_line''' to draw a line chart
 * '''geom_boxplot''' to draw a box plot
 |-
@@ Line 340: / Line 326: @@
 * How to create plots using '''aesthetic'''
 * Tuning parameters in '''aesthetic'''
 |-
@@ Line 346: / Line 331: @@
 Assignment
 || We now suggest an assignment.
 * Using built-in data set '''mtcars, '''draw a bar chart from the object '''cyl'''.
 * Add suitable labels to this bar chart.
 |-