Sakinashaikh at 10:50, 22 May 2020

2020-05-22T10:50:04Z

Sakinashaikh at 10:49, 22 May 2020

2020-05-22T10:49:45Z

Sakinashaikh: Created page with " {| border =1 |'''Time''' |'''Narration''' |- || 00:01 || Welcome to this tutorial on '''Introduction to ggplot2'''. |- || 00:07 || In this tutorial, we will learn abou..."

2020-05-22T10:49:14Z

Created page with " {| border =1 |'''Time''' |'''Narration''' |- || 00:01 || Welcome to this tutorial on '''Introduction to ggplot2'''. |- || 00:07 || In this tutorial, we will learn abou..."

New page

{| border =1
|'''Time'''
|'''Narration'''

|-
|| 00:01
|| Welcome to this tutorial on '''Introduction to ggplot2'''.

|-
|| 00:07
|| In this tutorial, we will learn about

|-
|| 00:11
|| Need for '''data visualization'''

|-
|| 00:15
|| Basic '''plot function''' in '''R'''

|-
|| 00:18
|| '''ggplot2 package'''

|-
|| 00:21
|| To understand this tutorial, you should know,

|-
|| 00:25
|| Basics of Statistics and

|-
|| 00:28
|| '''Data frames'''

|-
|| 00:31
|| If not, please locate the relevant tutorials on '''R''' on this website.

|-
|| 00:38
|| This tutorial is recorded on

|-
|| 00:40
|| '''Ubuntu Linux ''' OS version 16.04

|-
|| 00:46
|| '''R''' version 3.4.4

|-
|| 00:50
|| '''RStudio''' version 1.1.463

|-
|| 00:56
|| Install '''R''' version 3.2.0 or higher.

|-
|| 01:02
|| For this tutorial, we will use,

|-
|| 01:05
|| A '''data frame moviesData.csv'''

|-
|| 01:10
|| And a '''script''' file '''ggPlots.R'''.

|-
|| 00:15
|| Please download these files from the '''Code files''' link of this tutorial.

|-
|| 01:21
|| I have downloaded and moved these files to '''ggPlots''' folder.

|-
|| 01:28
|| This folder is located in '''myProject''' folder on my '''Desktop'''.

|-
|| 01:33
|| I have also set '''ggPlots''' folder as my '''Working Directory'''.

|-
|| 01:40
|| Now let us learn about '''visualization'''.

|-
|| 01:44
|| '''Visualization''' is an important tool for '''insight generation'''.

|-
|| 01:50
|| It is used to understand the '''data structure''', identify '''outliers''' and find patterns.

|-
|| 01:57
|| There are 2 methods of '''data visualization''' in '''R''':

|-
|| 02:03
|| Basics graphics and

|-
|| 02:05
|| Grammar of graphics (popularly known as '''ggplot2''')

|-
|| 02:11
|| Let us switch to '''RStudio'''.

|-
|| 02:14
|| Open the '''script ggPlots.R''' in '''RStudio'''.

|-
|| 02:20
|| Let us run this '''script''' by clicking on the '''Source''' button.

|-
|| 02:26
|| '''movies data frame''' is loaded in the '''workspace'''.

|-
|| 02:30
|| This '''data frame''' will be used later in this tutorial.

|-
|| 02:35
|| First, we will plot a '''sine''' curve by taking equally spaced samples.

|-
|| 02:42
|| In the '''Source''' window, type the following '''commands'''.

|-
|| 02:47
|| Here, we have used the '''seq function''' to generate a sequence.

|-
|| 02:53
||This sequence is from '''minus pi''' to '''plus pi''' with an interval of zero point one.

|-
|| 03:00
|| In '''plot command''', the first '''argument''' is '''x''' and the second '''argument y''' is '''Sine of x'''.

|-
|| 03:12
||Save the '''script''' and run the last three lines of code by pressing '''Ctrl + Enter''' keys simultaneously.

|-
|| 03:23
|| A plot of '''sine''' curve appears in the '''Plots''' window.

|-
|| 03:27
|| In the '''Plots''' window, click on the '''Zoom''' button to maximize the plot.

|-
|| 03:34
|| Now we will add some more layers in this '''plot'''.

|-
|| 03:39
|| Click on '''Close ''' button to close this plot.

|-
|| 03:43
||In the '''Source''' window, type the following '''commands'''.

|-
|| 03:48
|| Here, we have added '''main''' and '''ylab arguments''' to the '''plot function'''.

|-
|| 03:55
||Run the current line.

|-
|| 03:57
||In the '''Plots''' window, click on '''Zoom''' button to maximize the plot.

|-
|| 04:04
|| The title of the '''plot''' and label of Y-axis have been added to the plot.

|-
|| 04:10
|| Close this plot.

|-
|| 04:13
|| Now we will learn how to change the '''type''' of '''plot'''.

|-
|| 04:18
|| In the '''Source''' window, type the following '''commands'''.

|-
|| 04:23
|| Here, we have used the '''type argument''' and set it to '''l'''.

|-
|| 04:30
|| It means that the type of plot we need is '''lines'''.

|-
|| 04:36
|| '''col equal to blue''', changes the colour of the plot to blue.

|-
|| 04:42
|| Run the current line.

|-
|| 04:43
|| The '''type''' and '''color''' of the plot have been changed.

|-
|| 04:49
|| Now, we will plot one more graph on the same plot.

|-
|| 04:53
||Let us plot '''cosine''' of '''x '''along with '''sine''' of '''x''' on the same plot.

|-
|| 05:01
|| In the '''Source''' window, type the following '''commands'''.

|-
|| 05:05
|| This '''command''' plots '''sine''' of '''x''' using the '''plot function'''.

|-
|| 05:12
|| Next, we use '''lines function''' to plot '''cosine of x'''.

|-
|| 05:18
|| After the first line is plotted, the '''lines function''' is used.

|-
|| 05:23
||It takes an additional '''vector cos of x''' as an input to draw the second line in the plot.

|-
||05:32
|| Run the last two lines of code by pressing '''Ctrl+Enter''' keys simultaneously.

|-
|| 05:40
|| The two graphs appear in the same plot window.

|-
|| 05:45
||Here we can add a '''legend''' to the plot to differentiate between the multiple graphs.

|-
|| 05:52
||For this, we will use '''legend function'''.

|-
|| 05:56
|| In the '''Source''' window, type the following '''command'''.

|-
|| 06:00
|| I will resize the '''Source''' window.

|-
|| 06:04
|| The first '''argument''' refers to the coordinates for placing the '''legend''' in our plot.

|-
|| 06:12
||We have set the coordinates to '''topleft'''.

|-
|| 06:16
|| The second '''argument''' is the names to be given.

|-
|| 06:20
||Since we have plotted '''sine''' and '''cosine functions''', we will pass these two names as a '''vector'''.

|-
||06:28
|| Next, we have used the '''fill argument''' to specify the graphs by their colors.

|-
||06:35
||Recall that, '''sine function''' is plotted in blue and '''cosine function''' in red.

|-
|| 06:42
|| I will resize the '''Plots''' window.

|-
|| 06:45
|| Run the last three lines of code by pressing '''Ctrl+Enter''' keys simultaneously.

|-
|| 06:54
|| In the '''Plots''' window, click on '''Zoom''' button to maximize the plot.

|-
|| 07:00
|| The two plots with their names appear in the same graph.

|-
|| 07:05
|| Close the plot.

|-
|| 07:07
|| So far, we have discussed the basic graphics in '''R language'''.

|-
|| 07:13
|| Now, we will learn about the '''grammar of graphics''' by using '''ggplot2 package'''.

|-
|| 07:20
||'''ggplot2 package''' was created by '''Hadley Wickham''' in 2005.

|-
|| 07:26
|| It offers a powerful '''graphics language''' for creating elegant and complex plots.

|-
|| 07:34
|| Let us switch to '''RStudio'''.

|-
|| 07:37
|| I will resize the '''Plots''' window.

|-
|| 07:40
|| To use any '''package''' in '''R''', we need to install and then load it.

|-
|| 07:45
||As I have already installed '''ggplot2 package''', I will load this directly.

|-
|| 07:52
|| If you have not installed the '''package''', please use '''install dot packages function'''.

|-
|| 07:59
||Please make sure that you are connected to the Internet while installing the '''packages'''.

|-
|| 08:05
|| To load this '''package''', we will add the '''library''' at the top of the '''script'''.

|-
|| 08:11
|| In the '''Source '''window, scroll up to the top of the '''script'''.

|-
|| 08:16
|| Now, at the top of the '''script''', type '''library''' and '''ggplot2''' in parentheses.

|-
|| 08:26
|| Save the '''script '''and run this line.

|-
|| 08:31
|| Now, in the '''Source''' window, click on the next line after the '''legend function'''.

|-
|| 08:38
|| We will use '''movies data frame''' for exploring '''ggplot2 package'''.

|-
|| 08:44
|| Let us view the '''objects''' available in '''movies data frame'''.

|-
|| 08:50
|| In the '''Source''' window, type '''View''' and '''movies''' in parentheses.

|-
|| 08:56
|| Run the current line.

|-
|| 08:58
|| '''movies data frame''' opens in the '''Source''' window.

|-
|| 09:02
|| Now, we will create a simple '''scatter plot''' with two different '''objects''' of movies.

|-
|| 09:10
|| Remember, a '''scatter plot''' is a graph in which the values of two '''variables''' are plotted along the axes.

|-
|| 09:19
|| In the '''Source''' window, scroll from left to right to see the remaining '''objects''' of '''movies data frame'''.

|-
|| 09:28
|| Suppose, we want to visualize the correlation between '''critics_score''' and '''audience_score'''.

|-
|| 09:37
|| In the '''Source''' window, click on the '''script ggPlots.R'''

|-
|| 09:43
|| In the '''Source''' window, type the following '''command'''.

|-
|| 09:47
|| '''ggplot function''' takes three basic '''arguments''':

|-
|| 09:52
|| '''Data''' '''Aesthetics''' '''Geometry'''

|-
|| 09:56
|| In '''ggplot function''', we have used the following '''arguments''':

|-
|| 10:01
|| '''data''', which refers to the '''data set''' to be used for plotting.

|-
|| 10:06
|| We have set '''data''' equal to '''movies'''.

|-
|| 10:10
|| '''mapping, '''which is used to apply '''aesthetics mapping''' to the plot.

|-
|| 10:16
|| '''aes,''' which is used to specify the '''mapping''' of '''objects''' on X and Y axes.

|-
|| 10:23
|| We will learn more about aesthetics mapping later in this series.

|-
|| 10:28
|| '''geom '''underscore '''point''' is used to draw points defined by X and Y coordinates.

|-
|| 10:36
|| Run the current line.

|-
|| 10:39
|| '''Scatter plot''' appears in the '''Plots''' window.

|-
|| 10:42
|| In the '''Plots''' window, click on the '''Zoom''' button to maximize the plot.

|-
|| 10:49
|| We can see that there is a positive correlation between '''critics_score''' and '''audience_score'''.

|-
|| 10:56
|| Now we will learn how to save a plot generated by '''ggplot function'''.

|-
|| 11:03
|| Close this plot.

|-
|| 11:05
|| For saving the plots, there is a '''function''' named '''ggsave''' in '''ggplot2 package'''.

|-
|| 11:13
|| To know the syntax of '''ggsave function''', we will access the '''Help''' section in '''RStudio'''.

|-
||11:20
|| In the '''Console''' window, type question mark '''ggsave''' and press '''Enter'''.

|-
|| 11:27
|| I will resize the '''Help''' window.

|-
|| 11:30
|| The first '''argument''' in this '''function''' is the '''filename'''.

|-
|| 11:35
|| Next, there is the '''argument''' named '''plot''' which means the plot to be saved.

|-
|| 11:42
|| By default, it will save the last plot.

|-
|| 11:46
|| Click on the '''Plots '''window.

|-
|| 11:49
|| Let us save our '''scatter plot''' with a name '''scatter underscore plot''' in '''png format'''.

|-
|| 11:58
|| In the '''Source''' window, type the following '''command'''.

|-
|| 12:02
|| Save the '''script''' and run the current line.

|-
|| 12:07
|| Click on the '''Files '''tab.

|-
|| 12:10
|| The plot has been saved in our '''current working directory'''.

|-
|| 12:15
|| Let us summarize what we have learnt.

|-
|| 12:19
|| In this tutorial, we have learnt about,

|-
|| 12:23
|| Need for''' data visualization'''

|-
|| 12:26
|| Basic '''plot function''' in '''R'''

|-
|| 12:29
|| '''ggplot2 package'''

|-
|| 12:32
|| We now suggest an assignment.

|-
|| 12:36
|| Consider the '''built-in data set ''mtcars'''''. Find the numerical '''variables''' in this '''data set'''.

|-
|| 12:43
|| Make a '''scatter plot''' from the '''objects''' named '''mpg''' and '''wt''' in this '''data set'''.

|-
|| 12:51
|| Save the plot in '''.jpeg format'''.

|-
|| 12:56
|| The video at the following link summarises the Spoken Tutorial project.

|-
|| 13:01
|| Please download and watch it.

|-
|| 13:04
|| We conduct workshops using Spoken Tutorials and give certificates.

|-
|| 13:10
|| Please contact us.

|-
|| 13:13
|| Please post your timed queries in this forum.

|-
|| 13:17
|| Please post your general queries in this forum.

|-
|| 13:21
|| The '''FOSSEE '''team coordinates the '''TBC '''project.

|-
|| 13:24
||For more details, please visit these sites.

|-
|| 13:29
|| The Spoken Tutorial project is funded by , MHRD, Govt. of India

|-
|| 13:36
|| The script for this tutorial was contributed by Varshit Dubey (CoE Pune).

|-
|| 13:43
||This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching.

@@ Line 613: / Line 613: @@
 || 13:36
 || The script for this tutorial was contributed by Varshit Dubey (CoE Pune).
 |-
 || 13:43
 ||This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching.

@@ Line 121: / Line 121: @@
   || 02:14
   || Open the '''script ggPlots.R''' in '''RStudio'''.
   |-

R/C2/Introduction-to-ggplot2/English-timed - Revision history

Sakinashaikh at 10:50, 22 May 2020

Sakinashaikh at 10:49, 22 May 2020

Sakinashaikh: Created page with " {| border =1 |'''Time''' |'''Narration''' |- || 00:01 || Welcome to this tutorial on '''Introduction to ggplot2'''. |- || 00:07 || In this tutorial, we will learn abou..."