Difference between revisions of "PERL/C2/Hash-in-Perl/English-timed"

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|-
 
|-
 
| 00:01
 
| 00:01
|Welcome to the spoken tutorial on ''' Hash''' in '''Perl'''.
+
|Welcome to the spoken tutorial on ''' Hash''' in '''PERL'''.
  
 
|-
 
|-
 
| 00:05
 
| 00:05
| In this tutorial, we will learn about;
+
| In this tutorial, we will learn about:
  
 
|-
 
|-
 
|00:09
 
|00:09
|'''Hash''' in '''Perl''' and  
+
|'''Hash''' in PERL and  
 
   
 
   
 
|-
 
|-
 
|00:11
 
|00:11
| Accessing element of a '''hash'''  
+
| accessing element of a '''hash'''.
 
    
 
    
 
|-
 
|-
 
|00:14
 
|00:14
|For this tutorial, I am using  
+
|For this tutorial, I am using:
 
   
 
   
 
|-
 
|-
 
| 00:16
 
| 00:16
| ''' Ubuntu Linux12.04''' operating system  
+
|* '''Ubuntu Linux 12.04''' operating system  
  
 
|-
 
|-
 
| 00:21
 
| 00:21
|''' Perl 5.14.2''' and  
+
|* '''Perl 5.14.2''' and  
  
 
|-
 
|-
 
| 00:24
 
| 00:24
| ''' gedit''' Text Editor  
+
|* ''' gedit''' Text Editor.
  
 
|-
 
|-
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|-
 
|-
 
|00:30
 
|00:30
|To practise this tutorial, you should have knowledge of ''' Variables & Data Structures''' in '''Perl.'''
+
|To practice this tutorial, you should have knowledge of variables & data Structures in PERL.
 
   
 
   
 
|-
 
|-
 
| 00:38
 
| 00:38
| Knowledge of '''comments, loops, conditional statements''' and '''Arrays''' will be an added advantage.  
+
| Knowledge of '''comments, loops, conditional statements''' and '''arrays''' will be an added advantage.  
 
   
 
   
 
|-
 
|-
 
|00:46
 
|00:46
|Please go through the relevant spoken tutorials on the ''' spoken tutorial''' website.  
+
|Please go through the relevant spoken tutorials on the '''Spoken Tutorial''' website.  
  
 
|-
 
|-
 
|00:52
 
|00:52
|''' Hash''' is an unordered collection of data   
+
|'''Hash''' is an unordered collection of data.  
  
 
|-
 
|-
 
|00:56
 
|00:56
|It's a ''' key/value pair data structure '''
+
|It's a '''key/value''' pair data structure.
  
 
|-
 
|-
 
| 00:59
 
| 00:59
| '''Hash keys''' are unique  
+
| '''Hash''' keys are unique.
  
 
|-
 
|-
 
|01:01
 
|01:01
|However, ''' Hash''' can have duplicate values  
+
|However, '''Hash''' can have duplicate values.
  
 
|-
 
|-
 
|01:05
 
|01:05
| This is the declaration of a ''' hash''' .  
+
| This is the declaration of a '''hash'''.  
 
   
 
   
 
|-
 
|-
 
|01:08
 
|01:08
|Let us see how to get the value of a ''' key''' from '''hash. '''
+
|Let us see how to get the value of a ''' key''' from '''hash.'''
  
 
|-
 
|-
 
|01:12
 
|01:12
|The syntax for accessing the value of a ''' key''' is  
+
|The syntax for accessing the value of a ''' key''' is:
 
   
 
   
 
|-
 
|-
 
|01:17
 
|01:17
|''' dollar hashName open curly bracket single quote keyName single quote close curly bracket'''
+
|'''dollar hashName open curly bracket single quote keyName single quote close curly bracket'''.
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
| 01:31
 
| 01:31
|I have already typed the code in ''' perlHash dot pl''' file in '''gedit. '''
+
|I have already typed the code in '''perlHash dot pl''' file in '''gedit.'''
  
 
|-
 
|-
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|-
 
|-
 
|01:42
 
|01:42
| ''' Hash''' in ''' Perl''' is declared with '''percentage''' sign.  
+
| '''Hash''' in PERL is declared with '''percentage''' sign.  
  
 
|-
 
|-
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|-
 
|-
 
|01:53
 
|01:53
|Note: To access ''' key''' of '''hash''', one has to use '''dollar''' sign.  
+
|Note: To access '''key''' of '''hash''', one has to use dollar sign.  
 
   
 
   
 
|-
 
|-
 
|01:59
 
|01:59
|Press ''' Ctrl + S''' to save the file.  
+
|Press '''Ctrl + S''' to '''save''' the file.  
 
   
 
   
 
|-
 
|-
 
|02:02
 
|02:02
|Then switch to ''' terminal''' and execute the '''Perl script''' as  
+
|Then switch to terminal and execute the '''Perl script''' as:
 
   
 
   
 
|-
 
|-
 
|02:08
 
|02:08
|''' perl perlHash dot pl'''
+
|'''perl perlHash dot pl'''
  
 
|-
 
|-
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|-
 
|-
 
|02:24
 
|02:24
|The syntax for .
+
|The syntax for
  
 
|-
 
|-
 
|02:26
 
|02:26
|adding key is ''' dollar hashName open curly bracket '''
+
|adding key is '''dollar hashName open curly bracket'''
  
 
|-
 
|-
 
|02:30
 
|02:30
|''' single quote KeyName single quote'''  
+
|'''single quote KeyName single quote'''  
  
 
|-
 
|-
 
|02:34
 
|02:34
|''' close curly bracket equal to $value semicolon'''  
+
|'''close curly bracket equal to $value semicolon'''.
 
   
 
   
 
|-
 
|-
 
|02:40
 
|02:40
|deleting key is ''' delete dollar hashName open curly bracket'''  
+
|deleting key is '''delete dollar hashName open curly bracket'''  
  
 
|-
 
|-
 
|02:46
 
|02:46
|'''single quote KeyName single quote close curly bracket semicolon'''  
+
|'''single quote KeyName single quote close curly bracket semicolon'''.
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|03:23
 
|03:23
|''' delete''' keyword is used to delete the ''' key.'''  
+
|'''delete''' keyword is used to delete the '''key.'''  
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|  03:31
 
|  03:31
| Press ''' Ctrl+S''' to save the file.  
+
| Press ''' Ctrl+S''' to '''save''' the file.  
 
   
 
   
 
|-
 
|-
 
|03:35
 
|03:35
|Switch to the terminal and execute the ''' Perl script''' as  
+
|Switch to the terminal and execute the ''' Perl script''' as:
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
| 03:52
 
| 03:52
| Let us look at ''' sorting''' of a ''' hash keys''' and '''values.'''
+
| Let us look at '''sorting''' of a ''' hash keys''' and '''values.'''
  
 
|-
 
|-
 
| 03:57
 
| 03:57
| Syntax to ''' sort keys''' is  
+
| Syntax to '''sort keys''' is:
  
 
|-
 
|-
 
|04:00
 
|04:00
|''' sort open bracket keys percentage hashName close bracket semicolon '''
+
|'''sort open bracket keys percentage hashName close bracket semicolon'''.
 
   
 
   
 
|-
 
|-
 
|04:07
 
|04:07
|Similarly, we can '''sort hash values''' as  
+
|Similarly, we can sort '''hash values''' as:
  
 
|-
 
|-
 
|04:11
 
|04:11
|''' sort open bracket values percentage hashName close bracket semicolon'''  
+
|'''sort open bracket values percentage hashName close bracket semicolon'''.
 
   
 
   
 
|-
 
|-
 
|04:18
 
|04:18
|Let us understand ''' sorting''' functionality using a sample program.   
+
|Let us understand '''sorting''' functionality using a sample program.   
  
 
|-
 
|-
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|-
 
|-
 
| 04:30
 
| 04:30
|Type the code as displayed on the screen in your ''' sortHash dot pl''' file.  
+
|Type the code as displayed on the screen in your '''sortHash dot pl''' file.  
  
 
|-
 
|-
 
| 04:36
 
| 04:36
| Here we have declared ''' hash''' of '''address. '''
+
| Here we have declared '''hash''' of '''address.'''
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|04:59
 
|04:59
|Sorting can also be done on ''' numeric keys''' and/or '''values.'''  
+
|Sorting can also be done on '''numeric keys''' and/or '''values.'''  
 
   
 
   
 
|-
 
|-
 
|05:05
 
|05:05
|Save the file and switch to terminal.  
+
|'''Save''' the file and switch to terminal.  
  
 
|-
 
|-
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|-
 
|-
 
|08:21
 
|08:21
|Note: ''' Hash''' is an unordered collection of data.  
+
|Note: '''Hash''' is an unordered collection of data.  
  
 
|-
 
|-
 
|08:26
 
|08:26
|So, ''' keys''' returned will not be in the sequence defined at the time of creating '''hash.'''  
+
|So, '''keys''' returned will not be in the sequence defined at the time of creating '''hash.'''  
  
 
|-
 
|-
 
|08:33
 
|08:33
| The loop on ''' values''' works in a similar way.  
+
| The '''loop''' on '''values''' works in a similar way.  
  
 
|-
 
|-
 
|08:38
 
|08:38
|Press ''' Ctrl + S''' to save the file.  
+
|Press '''Ctrl + S''' to '''save''' the file.  
  
 
|-
 
|-
 
|08:41
 
|08:41
|Then, switch to terminal and execute the ''' Perl script''' as  
+
|Then, switch to terminal and execute the ''' Perl script''' as:
  
 
|-
 
|-
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|-
 
|-
 
|08:50
 
|08:50
|and press ''' Enter.'''
+
|and press '''Enter.'''
  
 
|-
 
|-
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|-
 
|-
 
|08:59
 
|08:59
|In this tutorial, we learnt -
+
|In this tutorial, we learnt
  
 
|-
 
|-
 
|09:01
 
|09:01
|''' Hash''' in '''Perl''' and  
+
|'''Hash''' in PERL and  
  
 
|-
 
|-
 
|09:03
 
|09:03
|Accessing elements of a '''hash'''  
+
|accessing elements of a '''hash'''  
  
 
|-
 
|-
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|-
 
|-
 
|09:15
 
|09:15
|And '''his/her percentage''' as the '''value'''.  
+
|and his/her percentage as the '''value'''.  
  
 
|-
 
|-
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|-
 
|-
 
|09:24
 
|09:24
|Then print the ''' percentage''' of each student.  
+
|Then print the percentage of each student.  
  
 
|-
 
|-
 
|09:29
 
|09:29
|Watch the video available at the following link
+
|Watch the video available at the following link.
 
   
 
   
 
|-
 
|-
 
|09:32
 
|09:32
|It summaries the Spoken Tutorial project
+
|It summarizes the Spoken Tutorial project.
 
   
 
   
 
|-
 
|-
 
|09:37
 
|09:37
|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.
 
   
 
   
 
|-
 
|-
 
| 09:42
 
| 09:42
|  The Spoken Tutorial Project Team  Conducts workshops using spoken tutorials
+
|  The Spoken Tutorial Project team: Conducts workshops using spoken tutorials.
 
   
 
   
 
|-
 
|-
 
|09:49
 
|09:49
|Gives certificates to those who pass an online test
+
|Gives certificates to those who pass an online test.
 
   
 
   
 
|-
 
|-
 
|09:53
 
|09:53
|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
 
   
 
   
 
|-
 
|-
 
| 10:02
 
| 10:02
|  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 513: Line 513:
 
|-
 
|-
 
|10:15
 
|10:15
|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.
 
   
 
   
 
|-
 
|-
 
| 10:26
 
| 10:26
| Hope you enjoyed this Perl tutorial.  
+
| Hope you enjoyed this PERL tutorial.  
 
   
 
   
 
|-
 
|-
 
|10:30
 
|10:30
|This is Amol signing off.
+
|This is Amol, signing off.
 
   
 
   
 
|-
 
|-

Revision as of 14:37, 13 May 2015

Time Narration
00:01 Welcome to the spoken tutorial on Hash in PERL.
00:05 In this tutorial, we will learn about:
00:09 Hash in PERL and
00:11 accessing element of a hash.
00:14 For this tutorial, I am using:
00:16 * Ubuntu Linux 12.04 operating system
00:21 * Perl 5.14.2 and
00:24 * gedit Text Editor.
00:26 You can use any text editor of your choice.
00:30 To practice this tutorial, you should have knowledge of variables & data Structures in PERL.
00:38 Knowledge of comments, loops, conditional statements and arrays will be an added advantage.
00:46 Please go through the relevant spoken tutorials on the Spoken Tutorial website.
00:52 Hash is an unordered collection of data.
00:56 It's a key/value pair data structure.
00:59 Hash keys are unique.
01:01 However, Hash can have duplicate values.
01:05 This is the declaration of a hash.
01:08 Let us see how to get the value of a key from hash.
01:12 The syntax for accessing the value of a key is:
01:17 dollar hashName open curly bracket single quote keyName single quote close curly bracket.
01:26 Let us understand hash using a sample program.
01:31 I have already typed the code in perlHash dot pl file in gedit.
01:37 Type the code as shown in your perlHash dot pl file.
01:42 Hash in PERL is declared with percentage sign.
01:47 These are the keys of hash.
01:49 And these are the values of hash.
01:53 Note: To access key of hash, one has to use dollar sign.
01:59 Press Ctrl + S to save the file.
02:02 Then switch to terminal and execute the Perl script as:
02:08 perl perlHash dot pl
02:11 and press Enter.
02:14 The output is as shown on the terminal.
02:19 Now let us see add and delete of keys from hash.
02:24 The syntax for:
02:26 adding key is dollar hashName open curly bracket
02:30 single quote KeyName single quote
02:34 close curly bracket equal to $value semicolon.
02:40 deleting key is delete dollar hashName open curly bracket
02:46 single quote KeyName single quote close curly bracket semicolon.
02:53 Now, let us understand this using a sample program.
02:58 I have already typed the code in hashKeyOperations dot pl file.
03:05 This is the declaration of hash.
03:08 We'll be adding, deleting the keys from this hash.
03:13 Here we are adding a key to an already created hash.
03:18 It is like assigning a value to a variable.
03:23 delete keyword is used to delete the key.
03:27 We need to pass the key to delete it.
03:31 Press Ctrl+S to save the file.
03:35 Switch to the terminal and execute the Perl script as:
03:40 perl hashKeyOperations dot pl
03:44 and press Enter.
03:47 Output will be as shown on the terminal.
03:52 Let us look at sorting of a hash keys and values.
03:57 Syntax to sort keys is:
04:00 sort open bracket keys percentage hashName close bracket semicolon.
04:07 Similarly, we can sort hash values as:
04:11 sort open bracket values percentage hashName close bracket semicolon.
04:18 Let us understand sorting functionality using a sample program.
04:24 Let me switch to sortHash dot pl on gedit.
04:30 Type the code as displayed on the screen in your sortHash dot pl file.
04:36 Here we have declared hash of address.
04:41 Here, to sort the keys we have used the sort inbuilt function, along with the keys function.
04:49 This will sort the hash keys in alphabetical order.
04:54 Similarly, we can use the sort function on values of hash.
04:59 Sorting can also be done on numeric keys and/or values.
05:05 Save the file and switch to terminal.
05:09 Execute the script by typing perl sortHash dot pl and Press Enter
05:17 The output will be as shown on the terminal.
05:22 Now, let us see how to get all keys and values of hash.
05:27 Perl provides inbuilt function to fetch all the hash keys and values.
05:34 keys function is used to retrive all the keys of hash
05:40 values function returns values of all the keys whereas
05:46 each function iterates over hash and returns key/value pair from hash
05:53 Let us understand these using a sample program.
05:57 For this, we'll use perlHash dot pl script, which we have created earlier in this tutorial.
06:07 Type the following piece of code as shown on the screen;
06:12 Let us understand the code now.
06:15 keys function on hash, returns an array which contains all keys of hash.
06:22 values function on hash returns an array of values for all keys of hash.
06:30 each function returns the key/value pair.
06:34 Here, we have used the while loop.
06:36 It will iterate over each key/value pair of hash, that is returned by each function.
06:43 Press Ctrl+S to save the file.
06:48 Now, let us execute the script on the terminal by typing
06:53 perl perlHash dot pl
06:58 And Press Enter
07:01 The following output will be seen on the terminal.
07:05 Now let us see few other ways of looping over hash.
07:10 We can use foreach loop to iterate over each key of hash.
07:15 Then perform a set of actions on the value of a key.
07:20 The syntax is as displayed on the screen.
07:24 Here, each iteration of foreach loop will assign key from hash to $variable.
07:32 Then it will use that $variable to fetch the value or to perform a set of actions.
07:40 Similarly, we can loop over hash values as shown on the screen.
07:47 We will look at sample program.
07:49 So, let me switch to loopingOverHash dot pl in gedit.
07:55 Type the following piece of code as shown in your loopingOverHash dot pl
08:02 This piece of code returns single key of hash.
08:07 Here in our case,
08:09 1st time dollar key ($key) contains the Department as key.
08:15 In the next iteration of foreach, Name key is returned.
08:21 Note: Hash is an unordered collection of data.
08:26 So, keys returned will not be in the sequence defined at the time of creating hash.
08:33 The loop on values works in a similar way.
08:38 Press Ctrl + S to save the file.
08:41 Then, switch to terminal and execute the Perl script as:
08:46 perl loopingOverHash dot pl
08:50 and press Enter.
08:53 The following output is displayed on the terminal.
08:58 Let us summarize.
08:59 In this tutorial, we learnt:
09:01 Hash in PERL and
09:03 accessing elements of a hash
09:05 using sample programs.
09:08 Here is assignment for you -
09:11 Declare hash having student name as key
09:15 and his/her percentage as the value.
09:18 Loop over hash using keys, values and each function
09:24 Then print the percentage of each student.
09:29 Watch the video available at the following link.
09:32 It summarizes the Spoken Tutorial project.
09:37 If you do not have good bandwidth, you can download and watch it.
09:42 The Spoken Tutorial Project team: Conducts workshops using spoken tutorials.
09:49 Gives certificates to those who pass an online test.
09:53 For more details, please write to contact at: spoken hyphen tutorial dot org
10:02 Spoken Tutorial project is a part of the "Talk to a Teacher" project.
10:06 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:15 More information on this mission is available at spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
10:26 Hope you enjoyed this PERL tutorial.
10:30 This is Amol, signing off.
10:33 Thanks for joining.

Contributors and Content Editors

Gaurav, Nancyvarkey, PoojaMoolya, Sandhya.np14