Difference between revisions of "Linux-AWK/C2/Basics-of-awk/English-timed"

From Script | Spoken-Tutorial
Jump to: navigation, search
m (Nancyvarkey moved page Linux/C3/Basics-of-awk/English-timed to Linux-AWK/C2/Basics-of-awk/English-timed without leaving a redirect: New series)
Line 5: Line 5:
 
|-
 
|-
 
|  00:01
 
|  00:01
−
| Welcome to the spoken tutorial on  '''awk''' command.
+
| Welcome to the '''spoken tutorial''' on  ''''awk' command'''.
  
 
|-
 
|-
 
|00:05  
 
|00:05  
−
|  In this tutorial we will learn '''awk command.'''
+
|  In this tutorial, we will learn '''awk command.'''
  
 
|-
 
|-
Line 18: Line 18:
 
| 00:12
 
| 00:12
 
| To record this tutorial, I am using:
 
| To record this tutorial, I am using:
−
Ubuntu Linux 12.04 OS
+
'''Ubuntu Linux''' version '''12.04 OS''',
−
GNU BASH v. 4.2.24
+
'''GNU BASH''' version '''4.2.24'''
  
 
|-
 
|-
 
| 00:23
 
| 00:23
−
| Please note, GNU Bash version 4 or above is recommended to practice this tutorial.
+
| Please note, '''GNU Bash''' version 4 or above is recommended to practice this tutorial.
  
 
|-
 
|-
Line 35: Line 35:
 
|-
 
|-
 
| 00:38
 
| 00:38
−
| It is named after its authors, Aho, Weinberger and Kernighan.
+
| It is named after its authors- Aho, Weinberger and Kernighan.
  
 
|-
 
|-
Line 43: Line 43:
 
|-
 
|-
 
| 00:46
 
| 00:46
−
| It operates at the field level of a record.  
+
| It operates at the '''field''' level of a '''record.'''
  
 
|-
 
|-
 
| 00:51
 
| 00:51
−
| So, it can easily access and edit the individual fields of the record.
+
| So, it can easily access and '''edit''' the individual '''field'''s of the '''record'''.
  
 
|-
 
|-
Line 63: Line 63:
 
|-
 
|-
 
| 01:09
 
| 01:09
−
| Now open the '''terminal''' window by pressing '''Ctrl + Alt''' and '''T''' keys simultaneously on your keyboard.
+
| Now, open the '''terminal''' window by pressing '''Ctrl + Alt''' and '''T''' keys simultaneously on your keyboard.
  
 
|-
 
|-
 
| 01:17
 
| 01:17
−
| Let us see how to print using '''awk command.'''  
+
| Let us see how to '''print''' using '''awk command.'''  
  
 
|-
 
|-
Line 87: Line 87:
 
|-
 
|-
 
| 01:49
 
| 01:49
−
| The action here is print.  
+
| The action here is '''print'''.  
  
 
|-
 
|-
Line 95: Line 95:
 
|-
 
|-
 
| 01:56
 
| 01:56
−
| Say, we want to print records of students with name "Mira."
+
| Say, we want to '''print record'''s of students with name "Mira."
  
 
|-
 
|-
Line 116: Line 116:
 
|-
 
|-
 
| 02:40
 
| 02:40
−
| For example,
+
| For example-
  
 
|-
 
|-
 
| 02:42
 
| 02:42
−
| Mira with M I R A
+
| Mira with M I R A,
  
 
|-
 
|-
Line 128: Line 128:
 
|-
 
|-
 
| 02:47
 
| 02:47
−
| and Meeraa with M double E R double A
+
| and Meeraa with M double E R double A.
  
 
|-
 
|-
Line 136: Line 136:
 
|-
 
|-
 
| 02:58
 
| 02:58
−
| Which means we can match multiple patterns separated by a '''PIPE'''.
+
| which means we can match multiple patterns separated by a '''PIPE'''.
 
|-
 
|-
 
|03:03
 
|03:03
−
|Let me clear the prompt.
+
|Let me clear the '''prompt'''.
  
 
|-
 
|-
 
|03:05
 
|03:05
−
|Now type:  '''awk space (within single quotes)(front slash) ‘/civil(PIPE) |electrical'''(front slash)'''space (opening curly brackets)/{print}(closing curly brackets)''' after the quotes space'''awkdemo.txt'''
+
|Now, type:  '''awk space (within single quotes)(front slash) ‘/civil(PIPE) |electrical'''(front slash)'''space (opening curly brackets)/{print}(closing curly brackets)''' after the quotes space'''awkdemo.txt'''
  
 
|-
 
|-
Line 155: Line 155:
 
|-
 
|-
 
| 03:31
 
| 03:31
−
|  Let us go back to our slides.  
+
|  Let us go back to our '''slide'''s.  
  
 
|-
 
|-
 
| 03:34
 
| 03:34
−
| Parameters: '''awk''' has some special parameters to identify individual fields of a line.  
+
| '''Parameter'''s: '''awk''' has some special parameters to identify individual '''field'''s of a line.  
  
 
|-
 
|-
Line 167: Line 167:
 
|-
 
|-
 
| 03:45
 
| 03:45
−
| Similarly we can have '''$2, $3''' and so on for respective fields.  
+
| Similarly, we can have '''$2, $3''' and so on for respective fields.  
  
 
|-
 
|-
Line 175: Line 175:
 
|-
 
|-
 
|03:56
 
|03:56
−
|come back to our terminal.
+
|Come back to our '''terminal'''.
  
 
|-
 
|-
Line 183: Line 183:
 
|-
 
|-
 
| 04:05
 
| 04:05
−
| In this case '''PIPE '''is called a '''delimiter.'''
+
| In this case, '''PIPE '''is called a '''delimiter.'''
  
 
|-
 
|-
Line 191: Line 191:
 
|-
 
|-
 
| 04:13
 
| 04:13
−
| A '''delimiter''' can also be a single '''white space.'''
+
| A '''delimiter''' can also be a single white '''space.'''
  
 
|-
 
|-
Line 215: Line 215:
 
|-
 
|-
 
| 05:04
 
| 05:04
−
|Say we only want to print two fields.
+
|Say, we only want to print two fields.
  
 
|-
 
|-
Line 239: Line 239:
 
|-
 
|-
 
| 05:32
 
| 05:32
−
| We can also provide a serial number by using a built-in variable '''NR'''.  
+
| We can also provide a serial number by using a '''built-in variable 'NR''''.  
  
 
|-
 
|-
 
| 05:40
 
| 05:40
−
| We will see more about built-in variables later.
+
| We will see more about '''built-in variable'''s later.
  
 
|-
 
|-
 
| 05:44
 
| 05:44
−
| Now Type '''awk''' space '''minus capital F within double quotes (Pipe)''' after the double quotes space ''' 'front-slash Pass front slash opening curly bracket printf (within double quotes)  "percentage sign 4d space percentage sign -25s space percentage sign  minus 15s space backslash n”,''' after the double quotes  '''NR, $2, $3 closing curly bracket' ''' after the single quote space '''awkdemo.txt'''   
+
| Now, type '''awk''' space '''minus capital F within double quotes (Pipe)''' after the double quotes space ''' 'front-slash Pass front slash opening curly bracket printf (within double quotes)  "percentage sign 4d space percentage sign -25s space percentage sign  minus 15s space backslash n”,''' after the double quotes  '''NR, $2, $3 closing curly bracket' ''' after the single quote space '''awkdemo.txt'''   
  
 
|-
 
|-
Line 255: Line 255:
 
|-
 
|-
 
| 06:37
 
| 06:37
−
| Here,  '''NR''' stands for number of records.  
+
| Here,  '''NR''' stands for number of '''record'''s.  
  
 
|-
 
|-
Line 263: Line 263:
 
|-
 
|-
 
| 06:45
 
| 06:45
−
| '''Name''' and '''Stream''' are '''strings'''. So we have used '''%s'''.  
+
| '''Name''' and '''Stream''' are '''strings'''. So, we have used '''%s'''.  
  
 
|-
 
|-
 
| 06:50
 
| 06:50
−
| Here '''25s''' will reserve 25 '''spaces''' for '''Name''' field.
+
| Here, '''25s''' will reserve 25 '''space'''s for '''Name''' field.
  
 
|-
 
|-
 
| 06:55
 
| 06:55
−
| '''15s''' will reserve 15 '''spaces''' for '''Stream''' field.
+
| '''15s''' will reserve 15 '''space'''s for '''Stream''' field.
  
 
|-
 
|-
 
| 07:01
 
| 07:01
−
| The '''minus sign''' is used to left justify the output.
+
| The '''minus sign''' is used to '''left justify''' the output.
  
 
|-
 
|-
Line 283: Line 283:
 
|-
 
|-
 
| 07:08
 
| 07:08
−
| Let us move back to our slides.
+
| Let us move back to our '''slide'''s.
  
 
|-
 
|-
 
| 07:10
 
| 07:10
−
| Let us summarize.  In this tutorial we learnt: * To print using awk
+
| Let us summarize.  In this tutorial, we learnt: to '''print''' using '''awk''',
  
 
|-
 
|-
 
| 07:16
 
| 07:16
−
| Regular expression in awk * To list the entries for a particular stream
+
| '''regular expression''' in '''awk''', 
 +
to list the entries for a particular '''stream''',
  
 
|-
 
|-
 
| 07:21
 
| 07:21
−
| To list only the second and the third fields
+
| to list only the second and the third '''field'''s,
  
 
|-
 
|-
 
| 07:24
 
| 07:24
−
| To display a formatted output.
+
| to display a formatted '''output'''.
  
 
|-
 
|-
Line 307: Line 308:
 
|-
 
|-
 
| 07:34
 
| 07:34
−
|  Watch the video available at the link shown below.
+
|  Watch the video available at the '''link''' shown below.
  
 
|-
 
|-
 
| 07:37
 
| 07:37
−
| It summarizes the Spoken Tutorial project.
+
| It summarizes the '''Spoken Tutorial''' project.
  
 
|-
 
|-
Line 319: Line 320:
 
|-
 
|-
 
|07:45
 
|07:45
−
|The Spoken Tutorial Project Team: Conducts workshops using spoken tutorials.
+
|The Spoken Tutorial Project Team: conducts workshops using spoken tutorials,
  
 
|-
 
|-
 
| 07:48
 
| 07:48
−
| Gives certificates to those who pass an online test.
+
| gives certificates to those who pass an online test.
  
 
|-
 
|-
 
| 07:52
 
| 07:52
−
| For more details, please write to contact@spoken-tutorial.org
+
| For more details, please write to '''contact@spoken-tutorial.org'''
  
 
|-
 
|-
 
| 07:58
 
| 07:58
−
|Spoken Tutorial Project is a part of the Talk to a Teacher project.
+
|'''Spoken Tutorial Project''' is a part of the '''Talk to a Teacher project'''.
  
 
|-
 
|-
 
| 08:01
 
| 08:01
−
| It is supported by the National Mission on Education through ICT,MHRD,Government of India.
+
| It is supported by the National Mission on Education through '''ICT, MHRD,''' Government of India.
  
 
|-
 
|-
 
| 08:07
 
| 08:07
−
| More information on this Mission is available at:  [http://spokentutorial.org\NMEICT-Intro]
+
| More information on this mission is available at:  [http://spokentutorial.org\NMEICT-Intro]
  
 
|-
 
|-
 
| 08:12
 
| 08:12
−
|This is Ashwini Patil from IIT Bombay, signning off. Thank you for joining.
+
|This is Ashwini Patil from '''IIT Bombay''', signing off. Thank you for joining.
  
 
|}
 
|}

Revision as of 16:45, 9 July 2019

Time Narration
00:01 Welcome to the spoken tutorial on 'awk' command.
00:05 In this tutorial, we will learn awk command.
00:09 We will do this through some examples.
00:12 To record this tutorial, I am using:

Ubuntu Linux version 12.04 OS, GNU BASH version 4.2.24

00:23 Please note, GNU Bash version 4 or above is recommended to practice this tutorial.
00:29 Let us start with an introduction to awk.
00:33 The awk command is a very powerful text manipulation tool.
00:38 It is named after its authors- Aho, Weinberger and Kernighan.
00:44 It can perform several functions.
00:46 It operates at the field level of a record.
00:51 So, it can easily access and edit the individual fields of the record.
00:56 Let us see some examples.
00:59 For demonstration purpose, we use the awkdemo.txt file.
01:04 Let us see the contents of awkdemo.txt file.
01:09 Now, open the terminal window by pressing Ctrl + Alt and T keys simultaneously on your keyboard.
01:17 Let us see how to print using awk command.
01:22 Type: awk space (within single quote) (front slash) '/Pass (front slash)/(opening curly bracket) {print (closing curly bracket)} (after the quotes) space awkdemo.txt
01:38 Press Enter.
01:40 Here, Pass is the selection criteria.
01:44 All the lines of the awkdemo where Pass occurs are printed.
01:49 The action here is print.
01:52 We can also use regular expressions in awk.
01:56 Say, we want to print records of students with name "Mira."
02:01 We would type:

awk space '/M (opening square bracket) [ ei (closing square bracket) ]*ra */{print}' space awkdemo.txt

02:27 Press Enter.
02:29 "*" will give one or more occurrences of previous character.
02:33 Thus, entries with more than one occurrence for i, e and a will be listed.
02:40 For example-
02:42 Mira with M I R A,
02:45 Meera with M double E R A
02:47 and Meeraa with M double E R double A.
02:52 awk supports the extended regular expressions (ERE)
02:58 which means we can match multiple patterns separated by a PIPE.
03:03 Let me clear the prompt.
03:05 electrical(front slash)space (opening curly brackets)/{print}(closing curly brackets) after the quotes spaceawkdemo.txt
03:23 Press Enter.
03:26 Now entries for both "civil" and "electrical" are given.
03:31 Let us go back to our slides.
03:34 Parameters: awk has some special parameters to identify individual fields of a line.
03:41 $1(Dollar 1) would indicate the first field.
03:45 Similarly, we can have $2, $3 and so on for respective fields.
03:53 $0 represents the entire line.
03:56 Come back to our terminal.
03:59 Note that each word is separated by PIPE in the file awkdemo.txt.
04:05 In this case, PIPE is called a delimiter.
04:09 A delimiter separates words from each other.
04:13 A delimiter can also be a single white space.
04:16 To specify a delimiter, we have to give - capital F flag followed by a delimiter.
04:24 Let us see. Type: awk space minus capital F space within double quotes PIPE space within single quote front-slash civil PIPE electrical front-slash opening curly bracket print space dollar0 closing curly bracket after the quotes space awkdemo.txt
04:51 Press Enter.
04:53 This prints the entire line since we have used $0.
04:58 Notice that names and stream of students are the second and third fields.
05:04 Say, we only want to print two fields.
05:08 We will replace $0 with $2 and $3 in the above command.
05:15 Press Enter .
05:18 Only two fields are shown.
05:21 Though it gives the right result, the display is all jagged and un-formatted.
05:26 We can provide formatted output by using the C style printf statement.
05:32 We can also provide a serial number by using a built-in variable 'NR'.
05:40 We will see more about built-in variables later.
05:44 Now, type awk space minus capital F within double quotes (Pipe) after the double quotes space 'front-slash Pass front slash opening curly bracket printf (within double quotes) "percentage sign 4d space percentage sign -25s space percentage sign minus 15s space backslash n”, after the double quotes NR, $2, $3 closing curly bracket' after the single quote space awkdemo.txt
06:33 Press Enter. We see the difference.
06:37 Here, NR stands for number of records.
06:41 Records are integers, hence we have written %d.
06:45 Name and Stream are strings. So, we have used %s.
06:50 Here, 25s will reserve 25 spaces for Name field.
06:55 15s will reserve 15 spaces for Stream field.
07:01 The minus sign is used to left justify the output.
07:05 This brings us to the end of this tutorial.
07:08 Let us move back to our slides.
07:10 Let us summarize. In this tutorial, we learnt: to print using awk,
07:16 regular expression in awk,

to list the entries for a particular stream,

07:21 to list only the second and the third fields,
07:24 to display a formatted output.
07:28 As an assignment, display roll no., stream and marks of Ankit Saraf.
07:34 Watch the video available at the link shown below.
07:37 It summarizes the Spoken Tutorial project.
07:40 If you do not have good bandwidth, you can download and watch it.
07:45 The Spoken Tutorial Project Team: conducts workshops using spoken tutorials,
07:48 gives certificates to those who pass an online test.
07:52 For more details, please write to contact@spoken-tutorial.org
07:58 Spoken Tutorial Project is a part of the Talk to a Teacher project.
08:01 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
08:07 More information on this mission is available at: [1]
08:12 This is Ashwini Patil from IIT Bombay, signing off. Thank you for joining.

Contributors and Content Editors

Nancyvarkey, PoojaMoolya, Pratik kamble, Ranjana, Sandhya.np14

Retrieved from "https://script.spoken-tutorial.org/index.php?title=Linux-AWK/C2/Basics-of-awk/English-timed&oldid=48077"