Difference between revisions of "Linux-AWK/C2/MultiDimensional-Array-in-awk/English-timed"

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(Created page with " {| border=1 | <center>'''Time'''</center> | <center>'''Narration'''</center> |- | 00:01 | Hello and Welcome to the spoken tutorial on creating '''multidimensional arrays'''...")
 
 
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|-
 
|-
 
| 00:01
 
| 00:01
−
| Hello and Welcome to the spoken tutorial on creating '''multidimensional arrays''' in '''awk'''.
+
| Hello and welcome to the '''spoken tutorial''' on creating '''multidimensional arrays in awk'''.
  
 
|-
 
|-
 
| 00:07
 
| 00:07
−
| In this tutorial we will learn to- Create '''multidimensional array '''in '''awk'''  and scan the '''multidimensional array'''
+
| In this tutorial, we will learn to-  
 +
create '''multidimensional array '''in '''awk'''  and  
 +
scan the '''multidimensional array'''.
  
 
|-
 
|-
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|-
 
|-
 
|00:21
 
|00:21
−
| To record this tutorial, I am using  '''Ubuntu Linux 16.04 Operating System '''and''' ''' '''gedit text editor 3.20.1'''
+
| To record this tutorial, I am using:  
 +
'''Ubuntu Linux 16.04 Operating System '''and
 +
'''gedit text editor 3.20.1'''
  
 
|-
 
|-
 
|00:33
 
|00:33
−
|You can use any text editor of your choice.
+
|You can use any '''text editor''' of your choice.
  
 
|-
 
|-
 
| 00:37
 
| 00:37
−
| To practice this tutorial, you should have gone through previous '''awk''' tutorials on '''array''' on this website.
+
| To practice this tutorial, you should have gone through previous '''awk''' tutorials on '''array''', on this website.
  
 
|-
 
|-
Line 48: Line 52:
 
|-
 
|-
 
|01:12
 
|01:12
−
|We know that in '''single dimensional arrays, '''an '''array element '''is identified by a single '''index'''.
+
|We know that in single dimensional arrays, an '''array element '''is identified by a single '''index'''.
  
 
|-
 
|-
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|-
 
|-
 
| 01:26
 
| 01:26
−
| However, in '''multidimensional array''', an '''element '''is identified by a sequence of multiple '''indices.'''
+
| However, in multidimensional array, an '''element '''is identified by a sequence of multiple indices.
  
 
|-
 
|-
 
|01:34
 
|01:34
−
|For example, a '''two dimensional array element '''is identified by a sequence of '''2 indices'''.
+
|For example, a two dimensional array element is identified by a sequence of 2 indices.
  
 
|-
 
|-
 
| 01:42
 
| 01:42
−
| Here, '''multiple indices '''are concatenated into a single '''string''', with a '''separator '''between them.  
+
| Here, multiple indices are concatenated into a single '''string''', with a '''separator '''between them.  
  
 
|-
 
|-
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|-
 
|-
 
| 01:55
 
| 01:55
−
| The combined '''string''' is used as a single '''index''' for a simple '''one dimensional array'''.
+
| The combined '''string''' is used as a single '''index''' for a simple one dimensional array.
  
 
|-
 
|-
 
| 02:01
 
| 02:01
−
| For example, Suppose we write '''multi within square brackets 4 comma 6 equal to value in double quotes'''
+
| For example, suppose we write '''multi within square brackets 4 comma 6 equal to value in double quotes'''.
  
 
|-
 
|-
 
|02:11
 
|02:11
−
|Here '''multi '''is the name of '''multi-dimensional array. '''
+
|Here, '''multi '''is the name of '''multi-dimensional array. '''
  
 
Then, the numbers '''4 '''and''' 6 '''are converted to a '''string'''.
 
Then, the numbers '''4 '''and''' 6 '''are converted to a '''string'''.
Line 86: Line 90:
 
|-
 
|-
 
|02:21
 
|02:21
−
|Suppose, the value of '''SUBSEP''' is '''hash symbol (#).'''
+
|Suppose, the value of '''SUBSEP''' is '''hash''' symbol (#).
  
 
|-
 
|-
 
| 02:26
 
| 02:26
−
|Then, those numbers are concatenated with a '''hash symbol (#)''' between them.
+
|Then, those numbers are concatenated with a '''hash (#)''' symbol between them.
  
 
|-
 
|-
 
| 02:32
 
| 02:32
−
| So, the '''array element multi within square brackets within double quotes 4 hash 6 '''is set to '''value within double quotes.'''
+
| So, the '''array element multi within square brackets within double quotes 4 hash 6 '''is set to '''value''' within double quotes.
  
 
|-
 
|-
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|-
 
|-
 
|02:50
 
|02:50
−
|It is actually a '''nonprinting character. '''
+
|It is actually a nonprinting character.  
  
 
It will not appear usually in most input data.
 
It will not appear usually in most input data.
Line 108: Line 112:
 
|-
 
|-
 
| 02:58
 
| 02:58
−
| Let us try to declare a '''two dimensional array '''as shown in the slide.
+
| Let us try to declare a two dimensional array as shown in the '''slide'''.
  
 
|-
 
|-
 
|03:03
 
|03:03
−
|Row 1 contains two '''elements A '''and '''B'''
+
|'''Row 1''' contains two '''elements A '''and '''B'''.
  
 
|-
 
|-
 
| 03:08
 
| 03:08
−
|Row 2 has '''two elements C '''and '''D'''
+
|'''Row 2''' has two '''elements C '''and '''D'''.
  
 
|-
 
|-
 
| 03:12
 
| 03:12
−
| Open the '''terminal''' by pressing '''Ctrl''', '''Alt''' and '''T''' keys
+
| Open the '''terminal''' by pressing '''Ctrl''', '''Alt''' and '''T''' keys.
  
 
|-
 
|-
 
| 03:17
 
| 03:17
−
| Go to the folder in which you downloaded and extracted the '''Code Files''' using '''cd command'''
+
| Go to the folder in which you have downloaded and extracted the '''Code Files''' using ''''cd' command'''.
  
 
|-
 
|-
 
| 03:24
 
| 03:24
−
| Now define the '''array '''as follows. Type the command carefully as shown here.
+
| Now, define the '''array '''as follows. Type the command carefully as shown here.
  
 
Then press '''Enter.'''
 
Then press '''Enter.'''
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|-
 
|-
 
|03:41
 
|03:41
−
| We do not get any output because we have not given anything to print in the code.
+
| We do not get any output because we have not given anything to print in the '''code'''.
  
 
|-
 
|-
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|-
 
|-
 
|03:50
 
|03:50
−
| Press the Up arrow key to get the previously executed command in the '''terminal'''.
+
| Press the '''up arrow''' key to get the previously executed '''command''' in the '''terminal'''.
  
 
|-
 
|-
 
| 03:56
 
| 03:56
−
| Just before the closing '''curly bracket''', type  '''semicolon''' space '''print space a within square brackets 2 comma 2'''
+
| Just before the closing curly bracket, type: '''semicolon space print space a within square brackets 2 comma 2'''.
  
−
Press '''Enter''' to execute the command.
+
Press '''Enter''' to '''execute''' the command.
  
 
|-
 
|-
 
|04:13
 
|04:13
−
| Notice, we get the output as '''capital D.'''
+
| Notice, we get the output as capital '''D'''.
  
 
|-
 
|-
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|-
 
|-
 
|04:28
 
|04:28
−
| We have already seen it in '''single-dimensional array '''earlier in this series.
+
| We have already seen it in single-dimensional array earlier in this series.
  
 
|-
 
|-
 
|04:34
 
|04:34
−
| We have to write the entire '''sequence '''of '''indices '''within '''parentheses ''' and separated by '''commas'''.
+
| We have to write the entire sequence of indices within parentheses and separated by commas.
  
 
|-
 
|-
Line 182: Line 186:
 
|-
 
|-
 
| 04:45
 
| 04:45
−
| I have already written a script named '''test_multi.awk'''
+
| I have already written a '''script''' named '''test_multi.awk'''.
  
 
|-
 
|-
Line 194: Line 198:
 
|-
 
|-
 
| 05:02
 
| 05:02
−
| Then I have written two '''if conditions'''.
+
| Then I have written two ''''if' condition'''s.
  
 
|-
 
|-
 
| 05:06
 
| 05:06
−
| The first '''if condition '''checks whether the '''element '''at the '''index one comma one, '''is present or not.
+
| The first '''if''' condition checks whether the '''element '''at the '''index one comma one, '''is present or not.
  
 
|-
 
|-
 
| 05:13
 
| 05:13
−
| We have to write the '''index '''for '''multidimensional array '''within '''parentheses'''.
+
| We have to write the '''index '''for '''multidimensional array '''within parentheses.
  
 
|-
 
|-
 
| 05:18
 
| 05:18
−
| If the '''condition '''is '''true''', it will print '''one comma one is present'''.
+
| If the condition is '''true''', it will print '''one comma one is present'''.
  
 
|-
 
|-
 
|05:23
 
|05:23
−
| Else it will print '''one comma one is absent.'''
+
| Else, it will print '''one comma one is absent.'''
  
 
|-
 
|-
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| Similarly, we will check for the presence of the '''element '''at '''index three comma one.'''
 
| Similarly, we will check for the presence of the '''element '''at '''index three comma one.'''
  
−
Let us execute the file.
+
Let us '''execute''' the file.
  
 
|-
 
|-
 
| 05:36
 
| 05:36
−
| Switch to the '''terminal '''and type '''awk space hyphen small f space test underscore multi dot awk '''and press '''Enter.'''
+
| Switch to the '''terminal '''and type: '''awk space hyphen small f space test underscore multi dot awk '''and press '''Enter.'''
  
 
|-
 
|-
 
| 05:49
 
| 05:49
−
| The output says '''one comma one is present '''and '''three comma one is absent.'''
+
| The output says: '''one comma one is present '''and '''three comma one is absent.'''
  
 
|-
 
|-
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|-
 
|-
 
| 06:11
 
| 06:11
−
| I have created a '''two-dimensional array matrix '''in the file '''2D-array.txt.'''
+
| I have created a two-dimensional array matrix in the file '''2D-array.txt.'''
  
 
|-
 
|-
 
|06:19
 
|06:19
−
| I have written a code named '''transpose.awk'''
+
| I have written a code named '''transpose.awk'''.
  
 
|-
 
|-
 
| 06:24
 
| 06:24
−
| First look at the '''action section''' of this '''awk script.'''
+
| First, look at the '''action''' section of this '''awk''' script.
  
 
|-
 
|-
 
| 06:29
 
| 06:29
−
| Here we are calculating the maximum number of '''fields''' in a '''row'''.
+
| Here, we are calculating the maximum number of '''fields''' in a '''row'''.
  
−
And stored the calculated value in the '''variable max_nf.'''
+
And, stored the calculated value in the '''variable max_nf.'''
  
 
|-
 
|-
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| As we know, '''NR '''is the number of current '''records '''processed by '''awk'''.
 
| As we know, '''NR '''is the number of current '''records '''processed by '''awk'''.
  
−
Value of '''NR '''is stored in '''max_nr variable.'''
+
Value of '''NR '''is stored in '''max_nr''' variable.
  
 
|-
 
|-
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|-
 
|-
 
| 07:11
 
| 07:11
−
|When '''awk '''is processing last '''record, max_nr '''will store the total number of '''records'''.
+
|When '''awk '''is processing the last record, '''max_nr '''will store the total number of records.
  
 
|-
 
|-
 
| 07:19
 
| 07:19
−
| Now we should read the data from '''input file '''and store the data into a '''two dimensional array'''.
+
| Now, we should read the data from input file and store the data into a two dimensional array.
  
 
|-
 
|-
 
| 07:26
 
| 07:26
−
|Inside the '''for loop, '''we have '''iterator variable x.'''
+
|Inside the ''''for' loop, '''we have '''iterator variable x.'''
  
 
|-
 
|-
 
| 07:31
 
| 07:31
−
|'''x '''will traverse from one to '''NF''', and '''x '''will be incremented by 1 after each '''iteration'''.
+
|'''x '''will traverse from one to '''NF''' and '''x '''will be incremented by 1 after each iteration.
  
 
|-
 
|-
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|-
 
|-
 
| 07:53
 
| 07:53
−
|For example, '''matrix of 1 comma 1 '''stores the value which is present at '''index 1 comma 1 '''from the '''input file.'''
+
|For example, '''matrix of 1 comma 1 '''stores the value which is present at '''index 1 comma 1 '''from the input file.
  
 
|-
 
|-
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|-
 
|-
 
| 08:10
 
| 08:10
−
|It will store entire data of '''input file '''into a '''two dimensional array''' format.
+
|It will store entire data of input file into a two dimensional array format.
  
 
|-
 
|-
 
| 08:16
 
| 08:16
−
| Now, let’s us look inside the '''END section. '''
+
| Now, let’s us look inside the '''END''' section.
  
 
|-
 
|-
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|-
 
|-
 
| 08:50
 
| 08:50
−
|So, there cannot be any special '''for statement '''to scan the '''multidimensional array. '''
+
|So, there cannot be any special ''''for' statement '''to '''scan''' the '''multidimensional array. '''
  
 
|-
 
|-
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|-
 
|-
 
| 09:00
 
| 09:00
−
|You can combine the '''for statement '''with the '''split function '''for this.
+
|You can combine the ''''for' statement '''with the '''split function '''for this.
  
 
|-
 
|-
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| Let us see what the '''split function''' is.
 
| Let us see what the '''split function''' is.
  
−
'''split function''' is used to chop up or split a '''string''' into pieces.
+
'''split function''' is used to chop up or split a '''string''' into pieces
  
 
|-
 
|-
 
| 09:14
 
| 09:14
−
|And place the various pieces into an '''array'''.
+
|and place the various pieces into an '''array'''.
  
 
|-
 
|-
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|-
 
|-
 
| 09:25
 
| 09:25
−
|Second '''argument '''specifies the name of the '''array '''where '''split '''will put the chopped pieces into.  
+
|Second '''argument '''specifies the name of the '''array '''where '''split() '''will put the chopped pieces into.  
  
 
|-
 
|-
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|-
 
|-
 
| 09:39
 
| 09:39
−
|The first piece is stored in ''' arr 1'''.
+
|The first piece is stored in ''' arr 1''',
  
 
|-
 
|-
 
| 09:43
 
| 09:43
−
|The second piece in '''arr 2''' and so forth.
+
|the second piece in '''arr 2''' and so forth.
  
 
|-
 
|-
 
| 09:48
 
| 09:48
−
| Suppose, we want to recover the original sequence of '''indices''' from an already created '''array'''.  
+
| Suppose, we want to recover the original sequence of indices from an already created '''array'''.  
  
 
How can we do this?
 
How can we do this?
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|-
 
|-
 
| 09:56
 
| 09:56
−
| I have written a code named '''multi_scan.awk'''
+
| I have written a code named '''multi_scan.awk'''.
  
 
|-
 
|-
 
| 10:02
 
| 10:02
−
| Entire code is written inside the '''BEGIN section'''.
+
| Entire code is written inside the '''BEGIN''' section.
  
 
|-
 
|-
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|-
 
|-
 
| 10:12
 
| 10:12
−
| Then we have the '''for loop '''with an '''iterator'''.
+
| Then we have the '''for''' loop with an '''iterator'''.
  
 
|-
 
|-
 
| 10:16
 
| 10:16
−
|The '''iterator '''will be set to each of the '''indices values '''for each '''iteration'''.
+
|The '''iterator '''will be set to each of the indices values for each iteration-
  
−
Say '''1,1''' then '''1,2 '''and so on.
+
say, '''1 comma 1''', then '''1 comma 2 '''and so on.
  
 
|-
 
|-
 
| 10:27
 
| 10:27
−
| The  '''split function '''breaks the '''iterator '''into pieces separated by '''SUBSEP.'''
+
| The  '''split() function '''breaks the '''iterator '''into pieces separated by '''SUBSEP.'''
  
 
|-
 
|-
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| So, '''arr[1] '''and '''arr[2] '''will contain the first '''index '''and second '''index '''respectively.
 
| So, '''arr[1] '''and '''arr[2] '''will contain the first '''index '''and second '''index '''respectively.
  
−
Let us execute this  file.
+
Let us '''execute''' this  file.
  
 
|-
 
|-
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|-
 
|-
 
| 11:01
 
| 11:01
−
| See the output; the original sequence of '''indices '''are recovered.
+
| See the output; the original sequence of indices are recovered.
  
 
|-
 
|-
 
| 11:07
 
| 11:07
−
| Let us summarize. In this tutorial we learnt to- Create a '''multidimensional array '''in '''awk''' and scan a '''multidimensional array'''
+
| Let us summarize. In this tutorial, we learnt to- create a '''multidimensional array '''in '''awk''' and  
 +
scan a '''multidimensional array'''.
  
 
|-
 
|-
 
| 11:18
 
| 11:18
−
| As an assignment, write an '''awk script '''to  rotate a '''two dimensional array '''by 90 degree and print the rotated '''matrix'''.
+
| As an assignment,  
 +
write an '''awk''' script to  rotate a two dimensional array by 90 degree and print the rotated '''matrix'''.
  
 
|-
 
|-
 
| 11:28
 
| 11:28
−
| 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.
Line 448: Line 454:
 
| The '''Spoken Tutorial Project''' team conducts workshops using spoken tutorials.  
 
| The '''Spoken Tutorial Project''' team conducts workshops using spoken tutorials.  
  
−
And gives certificates on passing online tests.
+
And, gives certificates on passing online tests.
  
 
|-
 
|-
Line 460: Line 466:
 
|-
 
|-
 
|11:53
 
|11:53
−
| Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.
+
| Spoken Tutorial Project is funded by '''NMEICT, MHRD''', Government of India.
  
 
More information on this mission is available at this link.
 
More information on this mission is available at this link.
Line 466: Line 472:
 
|-
 
|-
 
| 12:05
 
| 12:05
−
| The script has been contributed by Antara. And this is Praveen from IIT Bombay signing off.
+
| The script has been contributed by Antara. And this is Praveen from '''IIT Bombay''', signing off.
  
−
Thank you for joining
+
Thank you for joining.
  
 
|}
 
|}

Latest revision as of 20:53, 10 July 2019

Time
Narration
00:01 Hello and welcome to the spoken tutorial on creating multidimensional arrays in awk.
00:07 In this tutorial, we will learn to-

create multidimensional array in awk and scan the multidimensional array.

00:18 We will do this through some examples.
00:21 To record this tutorial, I am using:

Ubuntu Linux 16.04 Operating System and gedit text editor 3.20.1

00:33 You can use any text editor of your choice.
00:37 To practice this tutorial, you should have gone through previous awk tutorials on array, on this website.
00:45 You should have some basic knowledge of any programming language like C or C++.
00:52 If not, then please go through the corresponding tutorials on our website.
00:58 The files used in this tutorial are available in the Code Files link on this tutorial page.

Please download and extract them.

01:08 What is a multidimensional array in awk?
01:12 We know that in single dimensional arrays, an array element is identified by a single index.
01:19 For example, array week is identified by a single index, day.
01:26 However, in multidimensional array, an element is identified by a sequence of multiple indices.
01:34 For example, a two dimensional array element is identified by a sequence of 2 indices.
01:42 Here, multiple indices are concatenated into a single string, with a separator between them.
01:50 The separator is the value of the built-in variable SUBSEP.
01:55 The combined string is used as a single index for a simple one dimensional array.
02:01 For example, suppose we write multi within square brackets 4 comma 6 equal to value in double quotes.
02:11 Here, multi is the name of multi-dimensional array.

Then, the numbers 4 and 6 are converted to a string.

02:21 Suppose, the value of SUBSEP is hash symbol (#).
02:26 Then, those numbers are concatenated with a hash (#) symbol between them.
02:32 So, the array element multi within square brackets within double quotes 4 hash 6 is set to value within double quotes.
02:43 The default value of SUBSEP is the string within double quotes backslash 034.
02:50 It is actually a nonprinting character.

It will not appear usually in most input data.

02:58 Let us try to declare a two dimensional array as shown in the slide.
03:03 Row 1 contains two elements A and B.
03:08 Row 2 has two elements C and D.
03:12 Open the terminal by pressing Ctrl, Alt and T keys.
03:17 Go to the folder in which you have downloaded and extracted the Code Files using 'cd' command.
03:24 Now, define the array as follows. Type the command carefully as shown here.

Then press Enter.

03:35 We get a command prompt back without any error.

So, the array is defined.

03:41 We do not get any output because we have not given anything to print in the code.
03:47 Let us add the print statement.
03:50 Press the up arrow key to get the previously executed command in the terminal.
03:56 Just before the closing curly bracket, type: semicolon space print space a within square brackets 2 comma 2.

Press Enter to execute the command.

04:13 Notice, we get the output as capital D.
04:18 How to test if a particular index sequence exists in a given multidimensional array?
04:25 We can use in operator.
04:28 We have already seen it in single-dimensional array earlier in this series.
04:34 We have to write the entire sequence of indices within parentheses and separated by commas.
04:42 Let us see this in an example.
04:45 I have already written a script named test_multi.awk.
04:51 The same is available in the Code Files link of this tutorial page.
04:56 I have defined a 2 by 2 array as seen in our previous discussion.
05:02 Then I have written two 'if' conditions.
05:06 The first if condition checks whether the element at the index one comma one, is present or not.
05:13 We have to write the index for multidimensional array within parentheses.
05:18 If the condition is true, it will print one comma one is present.
05:23 Else, it will print one comma one is absent.
05:28 Similarly, we will check for the presence of the element at index three comma one.

Let us execute the file.

05:36 Switch to the terminal and type: awk space hyphen small f space test underscore multi dot awk and press Enter.
05:49 The output says: one comma one is present and three comma one is absent.
05:55 Let us take one more example.

Say, we want to create the transpose of a matrix.

06:02 The transpose of a given matrix is formed by interchanging the rows and columns of a matrix.

How can we do this?

06:11 I have created a two-dimensional array matrix in the file 2D-array.txt.
06:19 I have written a code named transpose.awk.
06:24 First, look at the action section of this awk script.
06:29 Here, we are calculating the maximum number of fields in a row.

And, stored the calculated value in the variable max_nf.

06:40 As we know, NR is the number of current records processed by awk.

Value of NR is stored in max_nr variable.

06:50 Awk will process the input file from the first record to the last record.
06:56 When awk is processing the first record, max_nr will be equal to 1.
07:03 While processing second record, max_nr will be 2 and it continues this way.
07:11 When awk is processing the last record, max_nr will store the total number of records.
07:19 Now, we should read the data from input file and store the data into a two dimensional array.
07:26 Inside the 'for' loop, we have iterator variable x.
07:31 x will traverse from one to NF and x will be incremented by 1 after each iteration.
07:39 For every value of x, $x(dollar x) represents the value at field x.
07:46 That value will be stored in array matrix at index NR comma x.
07:53 For example, matrix of 1 comma 1 stores the value which is present at index 1 comma 1 from the input file.
08:02 So, after awk has processed the entire input file with this code, matrix array will be completely formed.
08:10 It will store entire data of input file into a two dimensional array format.
08:16 Now, let’s us look inside the END section.
08:20 We have written a nested for loop to print the transpose of the matrix.
08:25 I assume your familiarity with basic C programming.

So, I am not explaining this portion of code in detail.

08:34 Pause the video here to look at the code in detail and understand on your own.
08:40 Now, we will learn how to scan a multidimensional array.
08:45 Awk does not have a multi-dimensional array in the truest sense.
08:50 So, there cannot be any special 'for' statement to scan the multidimensional array.
08:56 You can have multidimensional way to scan an array.
09:00 You can combine the 'for' statement with the split function for this.
09:05 Let us see what the split function is.

split function is used to chop up or split a string into pieces

09:14 and place the various pieces into an array.
09:18 The syntax is as follows. First argument contains the string to be chopped.
09:25 Second argument specifies the name of the array where split() will put the chopped pieces into.
09:33 The third argument mentions the separator that will be used to chop the string up.
09:39 The first piece is stored in arr 1,
09:43 the second piece in arr 2 and so forth.
09:48 Suppose, we want to recover the original sequence of indices from an already created array.

How can we do this?

09:56 I have written a code named multi_scan.awk.
10:02 Entire code is written inside the BEGIN section.
10:06 First we have created an array named a and assigned these values to it.
10:12 Then we have the for loop with an iterator.
10:16 The iterator will be set to each of the indices values for each iteration-

say, 1 comma 1, then 1 comma 2 and so on.

10:27 The split() function breaks the iterator into pieces separated by SUBSEP.
10:34 The pieces will be stored in the array arr.
10:38 So, arr[1] and arr[2] will contain the first index and second index respectively.

Let us execute this file.

10:48 Switch to the terminal and type- awk space hyphen small f space multi underscore scan dot awk

and press Enter.

11:01 See the output; the original sequence of indices are recovered.
11:07 Let us summarize. In this tutorial, we learnt to- create a multidimensional array in awk and

scan a multidimensional array.

11:18 As an assignment,

write an awk script to rotate a two dimensional array by 90 degree and print the rotated matrix.

11:28 The video at the following link summarises the Spoken Tutorial project.

Please download and watch it.

11:36 The Spoken Tutorial Project team conducts workshops using spoken tutorials.

And, gives certificates on passing online tests.

11:45 For more details, please write to us.
11:49 Please post your timed queries in this forum.
11:53 Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India.

More information on this mission is available at this link.

12:05 The script has been contributed by Antara. And this is Praveen from IIT Bombay, signing off.

Thank you for joining.

Contributors and Content Editors

PoojaMoolya, Sandhya.np14

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