Difference between revisions of "PERL/C2/Array-functions/English-timed"

From Script | Spoken-Tutorial
Jump to: navigation, search
Line 5: Line 5:
 
|-
 
|-
 
| 00:01
 
| 00:01
|Welcome to the spoken tutorial on '''Array Functions''' in '''Perl'''
+
|Welcome to the spoken tutorial on '''Array Functions''' in '''Perl'''.
  
 
|-
 
|-
 
| 00:06
 
| 00:06
| In this tutorial, we will learn about '''Array functions''' in '''Perl''', like  
+
| In this tutorial, we will learn about '''Array functions''' in '''Perl''', like:
  
 
|-
 
|-
 
|00:11
 
|00:11
|'''push '''
+
|* '''push '''
 
   
 
   
 
|-
 
|-
 
|00:11
 
|00:11
| '''pop'''  
+
|* '''pop'''  
 
    
 
    
 
|-
 
|-
 
|00:12
 
|00:12
|'''shift'''
+
|* '''shift'''
 
   
 
   
 
|-
 
|-
 
| 00:14
 
| 00:14
| '''unshift '''
+
|* '''unshift '''
  
 
|-
 
|-
 
| 00:15
 
| 00:15
|'''split'''
+
|* '''split'''
  
 
|-
 
|-
 
| 00:16
 
| 00:16
| '''splice '''
+
|* '''splice '''and
  
 
|-
 
|-
 
| 00:17
 
| 00:17
| and ''' join'''
+
|* '''join'''
  
 
|-
 
|-
 
| 00:18
 
| 00:18
| '''sort'''
+
|* '''sort'''
  
 
|-
 
|-
 
| 00:19
 
| 00:19
| '''qw'''
+
|* '''qw'''.
  
 
|-
 
|-
 
|00:20
 
|00:20
|I am using ''' Ubuntu Linux12.04''' operating system and '''Perl 5.14.2'''
+
|I am using ''' Ubuntu Linux 12.04''' operating system and '''Perl 5.14.2'''.
 
   
 
   
 
|-
 
|-
Line 61: Line 61:
 
|-
 
|-
 
|00:36
 
|00:36
|You should have basic knowledge of ''' Variables,  Data Structures'''  and '''Arrays''' in '''Perl'''
+
|You should have basic knowledge of variables,  Data Structures and '''Arrays''' in '''Perl'''.
  
 
|-
 
|-
Line 77: Line 77:
 
|-
 
|-
 
|00:57
 
|00:57
|These '''functions''' can perform various operations on an '''Array. '''
+
|These '''functions''' can perform various operations on an '''array. '''
  
 
|-
 
|-
 
| 01:02
 
| 01:02
| Let us first learn how to add and remove elements from last position of an '''Array'''.  
+
| Let us first learn how to add and remove elements from last position of an '''array'''.  
  
 
|-
 
|-
 
|01:08
 
|01:08
|'This can be done by using;
+
|This can be done by using:
  
 
|-
 
|-
 
|01:10
 
|01:10
| '''push function''' which adds an element at the last position of an '''Array'''  
+
| '''push''' function which adds an element at the last position of an '''array'''  
 
   
 
   
 
|-
 
|-
 
|01:15
 
|01:15
|and ''' pop function''' which removes an element from the last position of an '''Array'''  
+
|and ''' pop''' function which removes an element from the last position of an '''array'''.
  
 
|-
 
|-
 
|01:21
 
|01:21
| Let us understand '''push''' and '''pop functions''' by using a sample program.  
+
| Let us understand '''push''' and '''pop''' functions by using a sample program.  
 
   
 
   
 
|-
 
|-
 
|01:26
 
|01:26
|Open the terminal and type ''' gedit perlArray dot pl space ampersand '''
+
|Open the terminal and type: ''' gedit perlArray dot pl space ampersand '''
 
   
 
   
 
|-
 
|-
 
|01:33
 
|01:33
| And Press ''' Enter '''
+
| and press '''Enter'''.
  
 
|-
 
|-
 
| 01:36
 
| 01:36
|This will open ''' perlArray dot pl''' file in '''gedit'''.
+
|This will open 'perlArray dot pl' file in '''gedit'''.
  
 
|-
 
|-
 
|01:41
 
|01:41
|Type the code as shown on the screen  
+
|Type the code as shown on the screen.
 
   
 
   
 
|-
 
|-
 
|01:45
 
|01:45
| Here, we have declared an '''Array''' of length 3.  
+
| Here, we have declared an '''array''' of length 3.  
  
 
|-
 
|-
 
| 01:50
 
| 01:50
| '''push function''' will insert an element at the last position of this '''Array''' i.e after 3;
+
| '''push''' function will insert an element at the last position of this '''array''' i.e after 3  
 
   
 
   
 
|-
 
|-
 
|01:57
 
|01:57
|whereas, ''' pop function''' will remove an element from the last position of the '''Array'''.  
+
|whereas '''pop''' function will remove an element from the last position of the '''array'''.  
 
   
 
   
 
|-
 
|-
 
|02:04
 
|02:04
|In our case, 4 will be removed from the '''Array'''.  
+
|In our case, 4 will be removed from the '''array'''.  
 
   
 
   
 
|-
 
|-
 
|02:08
 
|02:08
|Press '''Ctrl + S''' to save the file.  
+
|Press '''Ctrl + S''' to '''save''' the file.  
 
   
 
   
 
|-
 
|-
 
|02:11
 
|02:11
|'''push function''' takes 2 '''arguments'''-  
+
|'''push''' function takes 2 '''arguments'''-  
 
   
 
   
 
|-
 
|-
 
|02:14
 
|02:14
|'''1st argument''' to the '''push function''', is the '''Array''' in which to add an '''element'''.  
+
|1st argument to the '''push''' function is the '''array''' in which to add an '''element'''.  
  
 
|-
 
|-
 
|02:20
 
|02:20
|''' 2nd argument'''  is the '''element''' which is to be '''pushed''' into the '''Array'''.  
+
| 2nd argument is the '''element''' which is to be pushed into the array.  
  
 
|-
 
|-
 
|02:25
 
|02:25
| The syntax of ''' pop function''' is as follows -
+
| The syntax of '''pop''' function is as follows
  
 
|-
 
|-
 
|02:29
 
|02:29
|''' pop function''' takes only one '''argument '''
+
|'''pop''' function takes only one '''argument.'''
 
   
 
   
 
|-
 
|-
 
|02:32
 
|02:32
|It is the '''Array''' from which an '''element''' needs to be removed.  
+
|It is the '''array''' from which an '''element''' needs to be removed.  
 
   
 
   
 
|-
 
|-
 
|02:36
 
|02:36
|Note: Both these functions work at ''' last position''' of an '''Array'''.  
+
|Note: Both these functions work at last position of an '''array'''.  
  
 
|-
 
|-
 
|02:41
 
|02:41
|The '''element''' removed by ''' pop function''' can be collected into another '''variable'''.
+
|The '''element''' removed by '''pop''' function can be collected into another variable.
  
 
|-
 
|-
 
|02:46
 
|02:46
|The syntax for this is ''' $variable space = space pop open bracket @myArray close bracket '''
+
|The syntax for this is '''$variable space = space pop open bracket @myArray close bracket '''.
  
 
|-
 
|-
Line 177: Line 177:
 
|-
 
|-
 
|03:01
 
|03:01
|Type '''perl perlArray dot pl''' and press '''Enter.'''
+
|Type: '''perl perlArray dot pl''' and press '''Enter.'''
 
   
 
   
 
|-
 
|-
Line 185: Line 185:
 
|-
 
|-
 
| 03:11
 
| 03:11
| Now, let us see how to add/remove an '''element''' from the ''' 1st position''' of an ''' Array'''.
+
| Now, let us see how to add/remove an '''element''' from the 1st position of an ''' array'''.
 
   
 
   
 
|-
 
|-
Line 193: Line 193:
 
|-
 
|-
 
|03:20
 
|03:20
|''' unshift function''' - which adds an '''element''' to an '''Array''' at the 1st position  
+
|'''unshift''' function which adds an '''element''' to an '''array''' at the 1st position.
 
   
 
   
 
|-
 
|-
 
|03:25
 
|03:25
|''' shift function''' - which removes the first '''element''' from an '''Array'''.  
+
|'''shift''' function which removes the first '''element''' from an '''array'''.  
 
   
 
   
 
|-
 
|-
Line 213: Line 213:
 
|-
 
|-
 
|  03:43
 
|  03:43
| ''' unshift''' function will insert an '''element''' at the first position i.e before 1  
+
|'''unshift''' function will insert an '''element''' at the first position i.e before 1.
 
   
 
   
 
|-
 
|-
 
|  03:52
 
|  03:52
| '''shift''' function will remove an ''' element''' from the first position.  
+
| '''shift''' function will remove an ''' element''' from the first position.  
 
   
 
   
 
|-
 
|-
 
| 03:57
 
| 03:57
| In our case, ''' zero''' will be removed.  
+
| In our case, '''zero''' will be removed.  
  
 
|-
 
|-
 
| 04:00
 
| 04:00
| Press '''Ctrl + S''' to save the file.  
+
| Press '''Ctrl + S''' to '''save''' the file.  
  
 
|-
 
|-
 
|04:03
 
|04:03
|The ''' unshift function''' takes 2  '''arguments '''-  
+
|The '''unshift''' function takes 2  '''arguments'''-  
 
   
 
   
 
|-
 
|-
 
|04:06
 
|04:06
|'''1st argument''' is the '''Array''' in which to add an '''element'''  
+
|1st argument is the '''array''' in which to add an '''element''',
  
 
|-
 
|-
 
|04:10
 
|04:10
|''' 2nd argument''' is the '''element''' to be added into the '''Array '''
+
|2nd argument is the '''element''' to be added into the '''array '''.
  
 
|-
 
|-
 
|04:15
 
|04:15
|''' shift function''' takes only one '''argument''' -  
+
|'''shift''' function takes only one '''argument''' -  
  
 
|-
 
|-
 
|04:18
 
|04:18
|This is the '''Array''' from which the '''element ''' needs to be removed.  
+
|This is the '''array''' from which the '''element ''' needs to be removed.  
 
   
 
   
 
|-
 
|-
 
| 04:22
 
| 04:22
| ''' Note:''' Both these functions works at '''first position''' of an '''Array'''.  
+
| Note: Both these functions work at first position of an '''array'''.  
  
 
|-
 
|-
 
| 04:27
 
| 04:27
| We can collect the '''element''' removed by '''shift function''' into some variable.  
+
| We can collect the '''element''' removed by '''shift''' function into some variable.  
 
   
 
   
 
|-
 
|-
 
|04:33
 
|04:33
|This syntax for this is ''' - $variable space =  space shift open bracket @myArray close bracket '''
+
|The syntax for this is: '''$variable space =  space shift open bracket @myArray close bracket'''.
 
   
 
   
 
|-
 
|-
 
|04:44
 
|04:44
|Then switch to the terminal and execute the ''' Perl script'''.  
+
|Then switch to the terminal and execute the '''Perl script'''.  
 
   
 
   
 
|-
 
|-
 
|04:48
 
|04:48
|Type ''' perl perlArray dot pl''' and press '''Enter'''.
+
|Type: '''perl perlArray dot pl''' and press '''Enter'''.
 
   
 
   
 
|-
 
|-
Line 273: Line 273:
 
|-
 
|-
 
|04:59
 
|04:59
|Now, let us see how to remove an ''' element''' from a specified position of an '''Array.'''  
+
|Now, let us see how to remove an ''' element''' from a specified position of an '''array.'''  
  
 
|-
 
|-
 
|05:05
 
|05:05
|''' splice function''' removes an ''' element''' from a specified position of an '''Array'''.  
+
|'''splice''' function removes an ''' element''' from a specified position of an '''array'''.  
  
 
|-
 
|-
 
|05:11
 
|05:11
|The ''' return value''' of this '''function''' is an ''' Array''' of removed elements.  
+
|The '''return value''' of this function is an '''array''' of removed elements.  
  
 
|-
 
|-
Line 289: Line 289:
 
|-
 
|-
 
|  05:21
 
|  05:21
|Go to the ''' perlArray dot pl ''' file, which we created earlier.  
+
|Go to the '''perlArray dot pl''' file which we created earlier.  
  
 
|-
 
|-
Line 297: Line 297:
 
|-
 
|-
 
|05:30
 
|05:30
| We need to provide ''' index'''  from where we want to remove the ''' elements''' and  
+
| We need to provide '''index'''  from where we want to remove the ''' elements''' and  
 
   
 
   
 
|-
 
|-
 
|  05:35
 
|  05:35
| the ''' offset''' upto which we want to remove the '''elements '''
+
| the '''offset''' up to which we want to remove the '''elements '''.
 
   
 
   
 
|-
 
|-
Line 309: Line 309:
 
|-
 
|-
 
|  05:44
 
|  05:44
| Then switch to the ''' terminal'''  and execute the ''' Perl script''' by typing -
+
| Then switch to the terminal and execute the ''' Perl script''' by typing
  
 
|-
 
|-
 
|  05:49
 
|  05:49
| ''' perl perlArray dot pl''' and press '''Enter.'''
+
| '''perl perlArray dot pl''' and press '''Enter.'''
  
 
|-
 
|-
 
|05:55
 
|05:55
|The output is as shown on the terminal
+
|The output is as shown on the terminal.
 
   
 
   
 
|-
 
|-
 
|  05:59
 
|  05:59
| Now let us look at few other ''' inbuilt functions''' of '''Arrays.'''
+
| Now, let us look at few other '''inbuilt functions''' of '''arrays.'''
 
   
 
   
 
|-
 
|-
 
|  06:04
 
|  06:04
| ''' split function''' is used to divide a '''string''' at a specified '''delimiter. '''
+
| '''split''' function is used to divide a '''string''' at a specified '''delimiter.'''
  
 
|-
 
|-
 
|06:10
 
|06:10
|The return value of this ''' function''' is an '''Array'''.  
+
|The return value of this function is an '''array'''.  
  
 
|-
 
|-
 
| 06:14
 
| 06:14
|The ''' elements''' of this '''Array''' are the divided portions of the '''string.'''  
+
|The '''elements''' of this '''array''' are the divided portions of the '''string.'''  
  
 
|-
 
|-
 
|06:19
 
|06:19
| ''' join function''' joins the '''elements''' of an '''Array''' , using the specified '''delimiter. '''
+
| '''join''' function joins the '''elements''' of an '''array''' using the specified '''delimiter.'''
  
 
|-
 
|-
 
|06:25
 
|06:25
|It returns a string of joined '''elements.'''  
+
|It returns a '''string''' of joined '''elements.'''  
  
 
|-
 
|-
 
| 06:28
 
| 06:28
| ''' sort function''' sorts an '''Array''' in alphabetical/numerical order.  
+
| '''sort''' function sorts an '''array''' in alphabetical/numerical order.  
  
 
|-
 
|-
 
| 06:34
 
| 06:34
| ''' qw function ''' returns an '''Array''' of words, separated by a '''white space'''.
+
| '''qw''' function returns an '''array''' of words, separated by a white '''space'''.
  
 
|-
 
|-
 
|  06:40
 
|  06:40
| Now let us understand all these ''' functions''' using a sample program.  
+
| Now let us understand all these functions using a sample program.  
  
 
|-
 
|-
 
|  06:45
 
|  06:45
|Switch to ''' terminal''' and type  
+
|Switch to terminal and type:
  
 
|-
 
|-
 
|06:48
 
|06:48
| ''' gedit arrayFunctions dot pl space ampersand and Press Enter'''
+
| '''gedit arrayFunctions dot pl space ampersand''' and press '''Enter'''.
 
   
 
   
 
|-
 
|-
Line 369: Line 369:
 
|-
 
|-
 
|07:00
 
|07:00
|In this case, each word of the ''' variable string''' will become an ''' element''' of an '''Array'''
+
|In this case, each word of the variable '''string''' will become an ''' element''' of an '''Array'''.
 
 
 
 
 
|-
 
|-
Line 377: Line 377:
 
|-
 
|-
 
|07:12
 
|07:12
|''' sort function''' will sort the '''elements''' of  an '''Array''' in alphabetical order.  
+
|'''sort''' function will sort the '''elements''' of  an array in alphabetical order.  
  
 
|-
 
|-
 
|07:19
 
|07:19
| '''qw function''' creates an '''Array''' of words separated by space.
+
| '''qw''' function creates an '''array''' of words separated by space.
  
 
|-
 
|-
 
|07:25
 
|07:25
| Let us understand each '''function.'''
+
| Let us understand each function.
 
   
 
   
 
|-
 
|-
 
|07:28
 
|07:28
|'''split function''' takes two '''arguments'''.
+
|'''split''' function takes two '''arguments'''.
  
 
|-
 
|-
 
|07:31
 
|07:31
|''' 1st argument''' is the ''' delimiter''' by which the ''' string''' needs to be split  
+
| 1st argument  is the '''delimiter''' by which the ''' string''' needs to be split,
  
 
|-
 
|-
 
|07:36
 
|07:36
|''' 2nd''' is the '''string''' which needs to be split.  
+
|'''2nd''' is the '''string''' which needs to be split.  
  
 
|-
 
|-
 
|07:39
 
|07:39
|'''Delimiters''' can be specified in ''' forward slash, single or double quotes. '''
+
|'''Delimiters''' can be specified in forward slash, single or double quotes.  
  
 
|-
 
|-
 
|07:45
 
|07:45
|''' join function''' takes 2 '''arguments'''.
+
|'''join''' function takes 2 '''arguments'''.
  
 
|-
 
|-
 
|07:48
 
|07:48
|1st is the '''delimiter''' by which the '''Array elements''' needs to be joined.   
+
|1st is the '''delimiter''' by which the array elements need to be joined.   
  
 
|-
 
|-
 
|07:53
 
|07:53
|2nd is the '''Array.'''  
+
|2nd is the '''array.'''  
  
 
|-
 
|-
 
|07:55
 
|07:55
|'''Delimiters'''  can be specified in '''single or double quotes. '''
+
|'''Delimiters'''  can be specified in single or double quotes.  
  
 
|-
 
|-
 
|07:58
 
|07:58
| ''' sort function''' takes a single '''argument''' , which is the '''Array''' that needs to be sorted.  
+
| '''sort''' function takes a single '''argument''' which is the '''array''' that needs to be sorted.  
  
 
|-
 
|-
 
|08:05
 
|08:05
|''' qw function''' returns an ''' Array''' of words, separated by ''' space.'''
+
|'''qw''' function returns an '''array''' of words, separated by '''space.'''
  
 
|-
 
|-
 
|08:11
 
|08:11
|It is not necessary to specify the word in ''' quotes''' , if written using '''qw. '''
+
|It is not necessary to specify the word in '''quotes''' if written using '''qw.'''
  
 
|-
 
|-
 
|08:17
 
|08:17
|Then switch to the terminal and execute the ''' Perl script''' by typing -
+
|Then switch to the terminal and execute the '''Perl script''' by typing
  
 
|-
 
|-
 
|08:23
 
|08:23
|''' perl arrayFunctions dot pl'''
+
|'''perl arrayFunctions dot pl'''
  
 
|-
 
|-
Line 453: Line 453:
 
|-
 
|-
 
|08:34
 
|08:34
|In this tutorial, we have learnt to -
+
|In this tutorial, we have learnt to
  
 
|-
 
|-
 
|08:36
 
|08:36
|add/remove ''' elements'''  from an '''Array '''
+
|* add/remove '''elements'''  from an '''array '''
  
 
|-
 
|-
 
|08:40
 
|08:40
|basic functions which can be performed on '''Array''' using sample programs  
+
|* basic functions which can be performed on '''array''' using sample programs.
  
 
|-
 
|-
Line 473: Line 473:
 
|-
 
|-
 
|08:54
 
|08:54
|split the above ''' string at '/ ' ''' (forward slash) '''delimiter '''
+
|* split the above '''string''' at '/ ' (forward slash) '''delimiter'''
  
 
|-
 
|-
 
|08:59
 
|08:59
|Add ''' https:// '''  at the start of an newly created '''Array'''   
+
|* Add ''' https:// '''  at the start of a newly created '''array'''   
  
 
|-
 
|-
 
|09:06
 
|09:06
|Remove ''' element “Perl” ''' from the '''Array '''
+
|* Remove '''element “Perl”''' from the '''array'''
  
 
|-
 
|-
 
|09:09
 
|09:09
|Declare number '''Array ''' and sort it  
+
|* Declare number '''array ''' and sort it.
  
 
|-
 
|-
 
|09:12
 
|09:12
|Watch the video available at the following link
+
|Watch the video available at the following link.
 
   
 
   
 
|-
 
|-
 
|09:15
 
|09:15
|It summaries the Spoken Tutorial project
+
|It summarizes the "Spoken Tutorial" project.
 
   
 
   
 
|-
 
|-
 
|09:19
 
|09:19
|If you do not have good bandwidth, you can download and watch it
+
|If you do not have good bandwidth, you can download and watch it.
 
   
 
   
 
|-
 
|-
 
| 09:24
 
| 09:24
|  The Spoken Tutorial Project Team Conducts workshops using spoken tutorials
+
|  The "Spoken Tutorial" project team: Conducts workshops using spoken tutorials.
 
   
 
   
 
|-
 
|-
 
|09:30
 
|09:30
|Gives certificates to those who pass an online  test
+
|Gives certificates to those who pass an online  test.
 
   
 
   
 
|-
 
|-
 
|09:34
 
|09:34
|For more details, please write to contact at spoken hyphen tutorial dot org
+
|For more details, please write to: contact at spoken hyphen tutorial dot org.
 
   
 
   
 
|-
 
|-
 
| 09:40
 
| 09:40
|  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.
 
   
 
   
 
|-
 
|-
Line 521: Line 521:
 
|-
 
|-
 
|09:51
 
|09:51
|More information on this Mission is available at spoken hyphen tutorial dot org slash NMEICT hyphen Intro
+
|More information on this mission is available at: spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
 
   
 
   
 
|-
 
|-
 
| 10:02
 
| 10:02
| Hope you enjoyed this Perl tutorial.  
+
| Hope you enjoyed this '''PERL''' tutorial.  
 
   
 
   
 
|-
 
|-
 
|10:04
 
|10:04
|This is Amol signing off.
+
|This is Amol, signing off.
 
   
 
   
 
|-
 
|-

Revision as of 10:58, 13 May 2015

Time Narration
00:01 Welcome to the spoken tutorial on Array Functions in Perl.
00:06 In this tutorial, we will learn about Array functions in Perl, like:
00:11 * push
00:11 * pop
00:12 * shift
00:14 * unshift
00:15 * split
00:16 * splice and
00:17 * join
00:18 * sort
00:19 * qw.
00:20 I am using Ubuntu Linux 12.04 operating system and Perl 5.14.2.
00:28 I will also be using the gedit Text Editor.
00:32 You can use any text editor of your choice.
00:36 You should have basic knowledge of variables, Data Structures and Arrays in Perl.
00:43 Knowledge of Comments, loops and conditional statements will be an added advantage.
00:48 Please go through the relevant spoken tutorials on the spoken tutorial website.
00:54 Perl provides certain inbuilt functions.
00:57 These functions can perform various operations on an array.
01:02 Let us first learn how to add and remove elements from last position of an array.
01:08 This can be done by using:
01:10 push function which adds an element at the last position of an array
01:15 and pop function which removes an element from the last position of an array.
01:21 Let us understand push and pop functions by using a sample program.
01:26 Open the terminal and type: gedit perlArray dot pl space ampersand
01:33 and press Enter.
01:36 This will open 'perlArray dot pl' file in gedit.
01:41 Type the code as shown on the screen.
01:45 Here, we have declared an array of length 3.
01:50 push function will insert an element at the last position of this array i.e after 3
01:57 whereas pop function will remove an element from the last position of the array.
02:04 In our case, 4 will be removed from the array.
02:08 Press Ctrl + S to save the file.
02:11 push function takes 2 arguments-
02:14 1st argument to the push function is the array in which to add an element.
02:20 2nd argument is the element which is to be pushed into the array.
02:25 The syntax of pop function is as follows:
02:29 pop function takes only one argument.
02:32 It is the array from which an element needs to be removed.
02:36 Note: Both these functions work at last position of an array.
02:41 The element removed by pop function can be collected into another variable.
02:46 The syntax for this is $variable space = space pop open bracket @myArray close bracket .
02:57 Now switch to the terminal and execute the Perl script.
03:01 Type: perl perlArray dot pl and press Enter.
03:07 The output is as shown on the terminal.
03:11 Now, let us see how to add/remove an element from the 1st position of an array.
03:18 This can be achieved using-
03:20 unshift function which adds an element to an array at the 1st position.
03:25 shift function which removes the first element from an array.
03:31 Let us understand this using a sample program.
03:35 I will open perlArray dot pl file which I have already created.
03:39 Type the following piece of code as shown on the screen.
03:43 unshift function will insert an element at the first position i.e before 1.
03:52 shift function will remove an element from the first position.
03:57 In our case, zero will be removed.
04:00 Press Ctrl + S to save the file.
04:03 The unshift function takes 2 arguments-
04:06 1st argument is the array in which to add an element,
04:10 2nd argument is the element to be added into the array .
04:15 shift function takes only one argument -
04:18 This is the array from which the element needs to be removed.
04:22 Note: Both these functions work at first position of an array.
04:27 We can collect the element removed by shift function into some variable.
04:33 The syntax for this is: $variable space = space shift open bracket @myArray close bracket.
04:44 Then switch to the terminal and execute the Perl script.
04:48 Type: perl perlArray dot pl and press Enter.
04:54 The output displayed on the terminal is as highlighted.
04:59 Now, let us see how to remove an element from a specified position of an array.
05:05 splice function removes an element from a specified position of an array.
05:11 The return value of this function is an array of removed elements.
05:17 Let us understand this using a sample program.
05:21 Go to the perlArray dot pl file which we created earlier.
05:26 Type the piece of code as shown on the screen.
05:30 We need to provide index from where we want to remove the elements and
05:35 the offset up to which we want to remove the elements .
05:39 In our case, the elements 5 and 6 will be removed.
05:44 Then switch to the terminal and execute the Perl script by typing:
05:49 perl perlArray dot pl and press Enter.
05:55 The output is as shown on the terminal.
05:59 Now, let us look at few other inbuilt functions of arrays.
06:04 split function is used to divide a string at a specified delimiter.
06:10 The return value of this function is an array.
06:14 The elements of this array are the divided portions of the string.
06:19 join function joins the elements of an array using the specified delimiter.
06:25 It returns a string of joined elements.
06:28 sort function sorts an array in alphabetical/numerical order.
06:34 qw function returns an array of words, separated by a white space.
06:40 Now let us understand all these functions using a sample program.
06:45 Switch to terminal and type:
06:48 gedit arrayFunctions dot pl space ampersand and press Enter.
06:55 Type the following piece of code as shown on screen.
07:00 In this case, each word of the variable string will become an element of an Array.
07:07 Here, each element of newArray will be joined by comma.
07:12 sort function will sort the elements of an array in alphabetical order.
07:19 qw function creates an array of words separated by space.
07:25 Let us understand each function.
07:28 split function takes two arguments.
07:31 1st argument is the delimiter by which the string needs to be split,
07:36 2nd is the string which needs to be split.
07:39 Delimiters can be specified in forward slash, single or double quotes.
07:45 join function takes 2 arguments.
07:48 1st is the delimiter by which the array elements need to be joined.
07:53 2nd is the array.
07:55 Delimiters can be specified in single or double quotes.
07:58 sort function takes a single argument which is the array that needs to be sorted.
08:05 qw function returns an array of words, separated by space.
08:11 It is not necessary to specify the word in quotes if written using qw.
08:17 Then switch to the terminal and execute the Perl script by typing:
08:23 perl arrayFunctions dot pl
08:26 and press Enter.
08:29 The following output is displayed on the screen.
08:33 Let us summarize.
08:34 In this tutorial, we have learnt to:
08:36 * add/remove elements from an array
08:40 * basic functions which can be performed on array using sample programs.
08:46 Here is assignment for you -
08:48 'script.spoken-tutorial.org/index.php/Perl'
08:54 * split the above string at '/ ' (forward slash) delimiter
08:59 * Add https:// at the start of a newly created array
09:06 * Remove element “Perl” from the array
09:09 * Declare number array and sort it.
09:12 Watch the video available at the following link.
09:15 It summarizes the "Spoken Tutorial" project.
09:19 If you do not have good bandwidth, you can download and watch it.
09:24 The "Spoken Tutorial" project team: Conducts workshops using spoken tutorials.
09:30 Gives certificates to those who pass an online test.
09:34 For more details, please write to: contact at spoken hyphen tutorial dot org.
09:40 "Spoken Tutorial" project is a part of the "Talk to a Teacher" project.
09:44 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
09:51 More information on this mission is available at: spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
10:02 Hope you enjoyed this PERL tutorial.
10:04 This is Amol, signing off.
10:06 Thanks for joining.

Contributors and Content Editors

Gaurav, PoojaMoolya, Sandhya.np14