View source for R/C2/Plotting-Histograms-and-Pie-Chart/English-timed



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|'''Time'''
|'''Narration'''

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|| 00:01 
|| Welcome to the spoken tutorial on '''Plotting Histograms and Pie Chart. '''

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|| 00:08
|| In this tutorial, we will learn how to: 

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|| 00:12
|| Plot '''histograms'''

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|| 00:15 
|| Plot '''pie chart'''

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|| 00:18
|| Save plots

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

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|| 00:25 
|| '''Data frames''' in '''R'''

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|| 00:28 
|| Basics of Statistics 

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

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|| 00:39 
|| This tutorial is recorded on

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|| 00:43 
|| '''Ubuntu Linux '''OS version '''16.04'''

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|| 00:48 
|| '''R''' version '''3.4.4'''

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|| 00:52 
|| '''RStudio''' version '''1.1.456'''

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|| 00:58 
|| Install '''R''' version '''3.2.0''' or higher. 

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|| 01:04
|| For this tutorial, we will use

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|| 01:07
||  A '''data frame moviesData.csv'''

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|| 01:12 
||  A '''script file myPlots.R'''.

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|| 01:17
|| Please download these files from the '''Code files''' link of this tutorial. 

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|| 01:24
|| I have downloaded and moved these files to '''Plots''' folder. 

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|| 01:30
|| This folder is located in '''myProject''' folder on my '''Desktop'''. 

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|| 01:36
|| I have also set this folder as my '''Working Directory.''' 

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|| 01:42
|| Let us switch to '''Rstudio'''.

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|| 01:46
|| Open the '''script myPlots.R '''in''' RStudio'''. 

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|| 01:52
|| Run this '''script''' by clicking on '''Source''' button. 

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|| 01:58
|| '''movies data frame''' opens in the '''Source''' window. 

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|| 02:03
|| This '''data frame''' has 600 rows and 31 columns. 

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|| 02:09
|| It means this '''data frame''' has 600 '''observations''' of 31 '''variables'''. 

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|| 02:17
|| To know about more this '''dataframe,''' please refer to the''' Additional Material section '''on this website.

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|| 02:25
|| In the '''Source''' window, scroll from left to right to see the remaining '''objects''' of '''movies data frame'''. 

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|| 02:34
|| Now we will learn how to plot a '''histogram''' of the '''object''' named '''runtime '''in '''movies'''. 

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|| 02:42
|| A '''histogram''' is 

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|| 02:44
|| A visual representation of the distribution of a '''dataset'''.

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|| 02:49
|| Used to plot the frequency of score occurrences in a continuous '''dataset'''

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|| 02:56
|| Let us switch to '''RStudio'''. 

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||02:59
|| Click on the '''script myPlots.R'''

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|| 03:04
|| In the '''Source''' window, type '''hist''', within parentheses '''movies''' dollar sign '''runtime'''. 

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|| 03:13
|| Save the '''script''' and run the current line by pressing '''Run '''button. 

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|| 03:20
|| The '''histogram''' appears in the '''Plots''' window. 

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|| 03:24
|| Click on '''Zoom''' to maximize this plot. 

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|| 03:29
|| In the '''histogram''' there are 9 '''bins'''. 

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|| 03:33
|| Height of a '''bin''' represents the number of observations lying in that interval.

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|| 03:40
|| Now, we will learn how to add labels to this '''histogram'''. 

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|| 03:46
|| Also, we will change the color of '''bins''' in this '''histogram'''. 

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|| 03:51
|| For this, we will add more '''arguments''' to the '''hist function'''. 

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|| 03:56
|| Close the '''histogram'''. 

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|| 03:59
|| In the '''Source''' window, type the following '''command'''. 

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|| 04:04
|| Here, we have used the following '''arguments''':

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|| 04:08
||  '''main''' for adding title to the '''histogram''' 

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|| 04:12
||  '''xlab''' for adding label to the x axis 

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|| 04:17
|| '''xlim''' to set the range of values on x axis 

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|| 04:23
|| '''col''' to set the color of '''bins''' 

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|| 04:28
|| Run the current line. 

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|| 04:31
|| In the '''Files''' and '''Plots''' window, click on '''Zoom''' to maximize the plot. 

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|| 04:38
|| The labels and the title of '''histogram''' have been changed. 

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|| 04:44
|| We can observe that most of the movies have the runtime of around 75 to 125 minutes. 

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|| 04:53
|| Now we will modify the number of '''breaks''' in the '''histogram'''. 

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|| 04:58
|| We can make the groups finer or coarser by modifying the number of '''breaks.'''

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|| 05:05
|| Close this plot. 

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|| 05:08
|| Let us add '''breaks argument''' in '''hist function''' and set it to 4. 

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|| 05:15
|| In the '''Source''' window, type the following '''command'''. 

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|| 05:20
|| Save the '''script''' and run the current line. 

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|| 05:25
|| In the '''Files''' and '''Plots''' window, click on '''Zoom''' to maximize the plot. 

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|| 05:31
|| Now, there are five '''bins''' in the '''histogram'''. 

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|| 05:35
|| Remember we had set '''breaks''' to be 4. 

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|| 05:40
|| Close the plot. 

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|| 05:43
|| In the '''Source''' window, click on '''movies'''. 

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|| 05:47
|| I am scrolling from right to left. 

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|| 05:52
|| Now, we will learn how to create a '''pie chart''' from the '''object genre''' in the '''movies data  frame'''. 

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|| 06:00
|| A '''pie chart''' is 

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|| 06:02
|| A circular chart. 

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|| 06:04
|| Divided into wedge-like sectors, illustrating proportion. 

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|| 06:10
|| The total value of the '''pie''' is always 100 percent.

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|| 06:15
|| Let us switch to '''RStudio'''. 

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|| 06:18
|| First, we will make a table of the number of different '''genres'''. 

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|| 06:24
|| For this, we use '''table function'''.

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|| 06:28
|| Click on the '''script myPlots.R'''

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|| 06:32
|| In the '''Source''' window, type the following '''command'''. 

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|| 06:36
|| Run the last two lines. 

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|| 06:40
|| We can see that there are 65 movies in '''Action & Adventure''' and 87 movies in '''Comedy'''. 

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|| 06:49
|| Now, we draw a '''pie chart''' with '''genreCount'''. 

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|| 06:54
|| Click on the '''script myPlots.R'''

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|| 06:58
|| In the '''Source''' window, type '''pie''' within parentheses '''genreCount'''. 

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|| 07:05
|| Run the current line. 

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|| 07:08
|| The '''pie chart''' appears in the '''Plots''' window. 

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|| 07:12
|| Click on '''Zoom''' to maximize this '''pie chart'''. 

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|| 07:17
|| We can see that '''Drama''' has largest share of '''movies'''. 

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|| 07:23
|| Now, we will change the color of border in this '''pie chart'''. 

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|| 07:28
|| For this, we will add more '''arguments''' to the '''pie function'''. 

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|| 07:33
|| Cose this plot. 

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|| 07:36
|| In the '''Source''' window, type the following '''command'''. 

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|| 07:40
|| Save the script and run the current line. 

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|| 07:45
|| The modified '''pie chart''' appears in the '''Plots''' window. 

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|| 07:50
|| Click on '''Zoom''' to maximize the plot.

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|| 07:54
|| Now, we will learn how to save this '''pie chart''' as an image on our computer. 

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|| 08:01
|| Close this plot. 

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|| 08:03
|| I am resizing the '''Files''' and '''Plots''' window. 

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|| 08:08
|| In the '''Plots''' window, click on '''Export'''. 

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|| 08:12
|| From the drop-down menu, select '''Save as Image. '''

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|| 08:17
|| A window named '''Save Plot as Image''' appears. 

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|| 08:22
|| You can select the format in which you want to save your image. 

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|| 08:28
|| I am saving it in '''JPEG''' format. 

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||08:33
|| Below the '''Image format''' option, you can select the directory where you want to save your image. 

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|| 08:41
|| By default, '''RStudio''' will save the image in the directory where the '''script''' has been placed. 

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|| 08:49
|| I will save the image in this folder. 

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|| 08:53
|| Below the directory, in the field '''File name''', you can write the name of the image to be saved. 

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|| 09:03
|| I am saving the image with the name '''pieChart''' with capital '''C'''. 

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|| 09:09
|| In the top right corner of this window, you can modify the dimensions of this image. 

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|| 09:17
|| I am setting the width to 650. 

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|| 09:21
|| Please make sure that '''Maintain aspect ratio''' is checked. 

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|| 09:26
|| Below '''Maintain aspect ratio''', click on '''Update Preview''' button. 

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|| 09:32
|| The image with larger dimensions is shown. 

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|| 09:37
|| Finally, click on '''Save'''. 

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|| 09:41
|| I am resizing the '''Files''' and '''Plots''' window. 



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|| 09:46
|| Now, click on the '''Files''' tab. 

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|| 09:50
|| The image '''pieChart.jpeg''' has been saved in the '''Plots''' folder.

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|| 09:57
|| Click on this image to see the saved '''pie chart'''. 

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|| 10:03
|| Let us summarize what we have learnt.

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|| 10:07
|| In this tutorial, we have learnt how to:

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|| 10:12
|| Plot '''histograms''' 

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||10:15
|| Plot '''pie chart'''

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|| 10:18
|| Save plots
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||10:21
|| We now suggest an assignment.

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||10:25
|| Read the file '''moviesData.csv'''. Create a '''histogram''' of the '''object''' named '''imdb_num_votes''' in this file. 

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||10:41
|| Create a '''pie chart''' of the '''object mpaa_rating'''. 

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||10:48
|| Save both the plots. 

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||10:51
|| The video at the following link summarises the Spoken Tutorial project.

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||10:56
||Please download and watch it.

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||11:00
|| We conduct workshops using Spoken Tutorials and give certificates.

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||11:06
||Please contact us.

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||11:09
|| Please post your timed queries in this forum.

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||11:14
|| Please post your general queries in this forum.

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||11:19
|| The '''FOSSEE '''team coordinates the '''TBC '''project.

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||11:23
||For more details, please visit these sites.

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||11:27
|| The Spoken Tutorial project is funded by NMEICT, MHRD, Govt. of India

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||11:34
|| The script for this tutorial was contributed by Tushar Bajaj (TISS Mumbai).

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||11:42
||This is Sudhakar Kumar from IIT Bombay signing off. Thanks for watching.

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