Difference between revisions of "Ruby/C3/for-and-each-Looping-Statements/English-timed"

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{| border=1
 
{| border=1
|| ''Time'''
+
|| '''Time'''
 
|| '''Narration'''
 
|| '''Narration'''
  
 
|-
 
|-
|  00.01
+
|  00:01
 
| Welcome to the tutorial on '''for''' and '''each Loops''' in Ruby.  
 
| Welcome to the tutorial on '''for''' and '''each Loops''' in Ruby.  
  
 
|-
 
|-
| 00.05
+
| 00:05
 
| In this tutorial we will learn  
 
| In this tutorial we will learn  
  
 
|-
 
|-
| 00.07
+
| 00:07
 
| Meaning of the term ''' “loop” '''
 
| Meaning of the term ''' “loop” '''
  
 
|-
 
|-
| 00.08
+
| 00:08
 
|The different kinds of loops in '''Ruby '''
 
|The different kinds of loops in '''Ruby '''
  
 
|-
 
|-
| 00.11
+
| 00:11
 
| Usage of ''' “for” ''' loop and  
 
| Usage of ''' “for” ''' loop and  
  
 
|-
 
|-
|  00.12
+
|  00:12
 
|Usage of ''' “each” ''' looping construct  
 
|Usage of ''' “each” ''' looping construct  
  
 
|-
 
|-
|  00.14
+
|  00:14
 
|Here we are using  
 
|Here we are using  
  
 
|-
 
|-
|  00.16
+
|  00:16
 
|  ''' Ubuntu''' version 12.04  
 
|  ''' Ubuntu''' version 12.04  
  
 
|-
 
|-
| 00.19
+
| 00:19
 
|''' Ruby '''1.9.3  
 
|''' Ruby '''1.9.3  
  
 
|-
 
|-
| 00.22
+
| 00:22
 
|To follow this tutorial, you must have ''' Internet''' Connection.   
 
|To follow this tutorial, you must have ''' Internet''' Connection.   
 
    
 
    
  
 
|-
 
|-
|  00.25
+
|  00:25
 
| You must also have knowledge of '''Linux'''  commands, ''' Terminal''' and ''' Text-editor.'''
 
| You must also have knowledge of '''Linux'''  commands, ''' Terminal''' and ''' Text-editor.'''
  
Line 53: Line 53:
  
 
|-
 
|-
| 00.30
+
| 00:30
 
|If not, for relevant tutorials, please visit our website.  
 
|If not, for relevant tutorials, please visit our website.  
  
 
|-
 
|-
|  00.34
+
|  00:34
 
|  Now let me explain what is referred to as a ''' “loop” ''' in '''Ruby. '''
 
|  Now let me explain what is referred to as a ''' “loop” ''' in '''Ruby. '''
  
 
|-
 
|-
| 00.38
+
| 00:38
 
|A '''loop''' is a command or set of commands that are executed a fixed number of times.  
 
|A '''loop''' is a command or set of commands that are executed a fixed number of times.  
  
 
|-
 
|-
| 00.44
+
| 00:44
 
|''' Ruby''' has the following main looping statements.  
 
|''' Ruby''' has the following main looping statements.  
  
 
|-
 
|-
| 00.47
+
| 00:47
 
|'''for'''
 
|'''for'''
  
 
|-
 
|-
| 00.48
+
| 00:48
 
| '''each '''
 
| '''each '''
  
 
|-
 
|-
| 00.49
+
| 00:49
 
|''' while'''
 
|''' while'''
  
 
|-
 
|-
|  00.49
+
|  00:49
 
| '''until'''
 
| '''until'''
  
 
|-
 
|-
| 00.50
+
| 00:50
 
|In this tutorial we will learn how to use the '''for''' and ''' each''' looping constructs.  
 
|In this tutorial we will learn how to use the '''for''' and ''' each''' looping constructs.  
  
 
|-
 
|-
| 00.55
+
| 00:55
 
| Before we begin, please create the following folders in your home directory,  
 
| Before we begin, please create the following folders in your home directory,  
  
 
|-
 
|-
| 01.02
+
| 01:02
 
| ttt,  ruby hyphen tutorial, looping hyphen statements.  
 
| ttt,  ruby hyphen tutorial, looping hyphen statements.  
  
 
|-
 
|-
| 01.07
+
| 01:07
 
| Please create the sub folders as mentioned there
 
| Please create the sub folders as mentioned there
  
 
|-
 
|-
| 01.11
+
| 01:11
 
|Now we have created the requisite folders.  
 
|Now we have created the requisite folders.  
  
 
|-
 
|-
| 01.13
+
| 01:13
 
|Let's move ahead.  
 
|Let's move ahead.  
  
 
|-
 
|-
| 01.15
+
| 01:15
 
|The syntax of the ''' “for” ''' loop in ''' Ruby''' is as follows:  
 
|The syntax of the ''' “for” ''' loop in ''' Ruby''' is as follows:  
  
  
 
|-
 
|-
|  01.19
+
|  01:19
 
| ''' for “variable” in “a collection of objects” '''
 
| ''' for “variable” in “a collection of objects” '''
  
  
 
|-
 
|-
|  01.22
+
|  01:22
 
|''' ruby code '''
 
|''' ruby code '''
  
 
|-
 
|-
|  01.23
+
|  01:23
 
| ''' end '''
 
| ''' end '''
  
 
|-
 
|-
| 01.25
+
| 01:25
 
| Let us try to understand it with an example.  
 
| Let us try to understand it with an example.  
  
 
|-
 
|-
|  01.28
+
|  01:28
 
| Create a new file in '''gedit''' as shown in the basic level ''' Ruby''' tutorials.  
 
| Create a new file in '''gedit''' as shown in the basic level ''' Ruby''' tutorials.  
  
 
|-
 
|-
| 01.32
+
| 01:32
 
|And name it ''' “for hyphen loop dot rb” '''
 
|And name it ''' “for hyphen loop dot rb” '''
  
  
 
|-
 
|-
| 01.36
+
| 01:36
 
|I already have a working example of the ''' “for” ''' loop.  
 
|I already have a working example of the ''' “for” ''' loop.  
  
 
|-
 
|-
| 01.39
+
| 01:39
 
|You can type the code as we go through this example.  
 
|You can type the code as we go through this example.  
  
 
|-
 
|-
|  01.44
+
|  01:44
 
|  I have declared a ''' “for” ''' loop in this example.  
 
|  I have declared a ''' “for” ''' loop in this example.  
  
 
|-
 
|-
| 01.47
+
| 01:47
 
|  We have a set of numbers 1 to 20.  
 
|  We have a set of numbers 1 to 20.  
  
 
|-
 
|-
| 01.50
+
| 01:50
 
| We declare a variable called “i” within the ''' “for” ''' loop.  
 
| We declare a variable called “i” within the ''' “for” ''' loop.  
  
  
 
|-
 
|-
|  01.55
+
|  01:55
 
|The variable “i” gets initialized to the first element in the set of numbers 1 to 20.  
 
|The variable “i” gets initialized to the first element in the set of numbers 1 to 20.  
  
 
|-
 
|-
|  02.00
+
|  02:00
 
| The ''' “for” '''  loop declaration causes the code to iterate over each element in the set 1 to 20.  
 
| The ''' “for” '''  loop declaration causes the code to iterate over each element in the set 1 to 20.  
  
 
|-
 
|-
|  02.07
+
|  02:07
 
| The ''' “puts” ''' method declared within the ''' “for” ''' loop is responsible for generating the output.  
 
| The ''' “puts” ''' method declared within the ''' “for” ''' loop is responsible for generating the output.  
  
  
 
|-
 
|-
| 02.14
+
| 02:14
 
|Now open the ''' terminal''' and type  
 
|Now open the ''' terminal''' and type  
  
 
|-
 
|-
|  02.17
+
|  02:17
 
| ''' ruby space  for hyphen loop dot rb ''' and see the output
 
| ''' ruby space  for hyphen loop dot rb ''' and see the output
  
 
|-
 
|-
| 02.22
+
| 02:22
 
|The output will be an '''array''' of numbers 1 to 20.  
 
|The output will be an '''array''' of numbers 1 to 20.  
  
 
|-
 
|-
|  02.26
+
|  02:26
 
| In this example, we declared a  ''' “for”''' loop for an inclusive range.  
 
| In this example, we declared a  ''' “for”''' loop for an inclusive range.  
  
 
|-
 
|-
| 02.31
+
| 02:31
 
| It included all numbers from 1 to 20.  
 
| It included all numbers from 1 to 20.  
  
 
|-
 
|-
| 02.35
+
| 02:35
 
| Next,  we shall look at implementing the ''' “for”''' loop for a non-inclusive range.  
 
| Next,  we shall look at implementing the ''' “for”''' loop for a non-inclusive range.  
  
 
|-
 
|-
| 02.41
+
| 02:41
 
|Continue to type the next part of the code.  
 
|Continue to type the next part of the code.  
  
 
|-
 
|-
| 02.44
+
| 02:44
 
|Non-inclusive means it will not include the last element in the collection of objects.  
 
|Non-inclusive means it will not include the last element in the collection of objects.  
  
 
|-
 
|-
| 02.49
+
| 02:49
 
|Here ''' “for”''' loop is implemented for a non-inclusive range of numbers 1 to 20.  
 
|Here ''' “for”''' loop is implemented for a non-inclusive range of numbers 1 to 20.  
  
 
|-
 
|-
|  02.55
+
|  02:55
 
| You will notice shortly that the number 20 will not be printed in the output.  
 
| You will notice shortly that the number 20 will not be printed in the output.  
  
 
|-
 
|-
| 02.59
+
| 02:59
 
|The last digit does not get included when you have 3 dots between numbers.  
 
|The last digit does not get included when you have 3 dots between numbers.  
  
 
|-
 
|-
| 03.04
+
| 03:04
 
| Now open the ''' terminal''' and type ''' ruby space for hyphen loop dot rb'''
 
| Now open the ''' terminal''' and type ''' ruby space for hyphen loop dot rb'''
  
 
|-
 
|-
| 03.13
+
| 03:13
 
|and see the output.  
 
|and see the output.  
  
 
|-
 
|-
| 03.17
+
| 03:17
 
|The output will still be an ''' array''' of numbers but will not include the number 20.  
 
|The output will still be an ''' array''' of numbers but will not include the number 20.  
  
  
 
|-
 
|-
| 03.22
+
| 03:22
 
| Now, you should be capable enough to write your own ''' “for”'''  loop.  
 
| Now, you should be capable enough to write your own ''' “for”'''  loop.  
  
 
|-
 
|-
| 03.27
+
| 03:27
 
|The syntax of the ''' “each”''' loop in ''' Ruby''' is as follows:  
 
|The syntax of the ''' “each”''' loop in ''' Ruby''' is as follows:  
  
 
|-
 
|-
|  03.31
+
|  03:31
 
| ''' “a collection of objects” dot each do item '''
 
| ''' “a collection of objects” dot each do item '''
  
 
|-
 
|-
|  03.36
+
|  03:36
 
| ''' ruby code end'''
 
| ''' ruby code end'''
  
 
|-
 
|-
|  03.38
+
|  03:38
 
|Let us try to understand it with an example.  
 
|Let us try to understand it with an example.  
  
  
 
|-
 
|-
|  03.42
+
|  03:42
 
| Create a new file in '''gedit''' as shown in the basic level '''Ruby''' tutorials.  
 
| Create a new file in '''gedit''' as shown in the basic level '''Ruby''' tutorials.  
  
 
|-
 
|-
| 03.46
+
| 03:46
 
|And name it '''each hyphen loop dot rb'''
 
|And name it '''each hyphen loop dot rb'''
  
 
|-
 
|-
|  03.50
+
|  03:50
 
|I already have a working example of the '''each''' loop.  
 
|I already have a working example of the '''each''' loop.  
  
 
|-
 
|-
|  03.53
+
|  03:53
 
|You can type the code as we go through this example.  
 
|You can type the code as we go through this example.  
  
 
|-
 
|-
| 03.58
+
| 03:58
 
|I have declared an '''each''' loop in this example.  
 
|I have declared an '''each''' loop in this example.  
  
 
|-
 
|-
|  04.03
+
|  04:03
 
|  We have a set of numbers 1 to 20.  
 
|  We have a set of numbers 1 to 20.  
  
 
|-
 
|-
| 04.06
+
| 04:06
 
|We declare a variable called “i” within the '''each''' loop.  
 
|We declare a variable called “i” within the '''each''' loop.  
  
  
 
|-
 
|-
| 04.11
+
| 04:11
 
| The “i” variable gets initialized to the first element in the set of numbers 1 to 20.  
 
| The “i” variable gets initialized to the first element in the set of numbers 1 to 20.  
 
   
 
   
  
 
|-
 
|-
| 04.17
+
| 04:17
 
|The '''each''' loop declaration causes the code to iterate over each element in the set 1 to 20.  
 
|The '''each''' loop declaration causes the code to iterate over each element in the set 1 to 20.  
  
 
|-
 
|-
| 04.23
+
| 04:23
 
|The ''' puts''' method declared within the ''' each'''  is responsible for generating the output.  
 
|The ''' puts''' method declared within the ''' each'''  is responsible for generating the output.  
  
 
|-
 
|-
| 04.30
+
| 04:30
 
|Now open the ''' terminal''' and type ''' ruby space each hyphen loop dot rb '''
 
|Now open the ''' terminal''' and type ''' ruby space each hyphen loop dot rb '''
  
 
|-
 
|-
|  04.39
+
|  04:39
 
| and see the output.  
 
| and see the output.  
  
  
 
|-
 
|-
| 04.43
+
| 04:43
 
|The output will be an array of numbers 1 to 20.  
 
|The output will be an array of numbers 1 to 20.  
  
  
 
|-
 
|-
|  04.46
+
|  04:46
 
| In the above example we declared an ''' each''' loop for an inclusive range.  
 
| In the above example we declared an ''' each''' loop for an inclusive range.  
  
  
 
|-
 
|-
|  04.51
+
|  04:51
 
|It included all numbers from 1 to 20.  
 
|It included all numbers from 1 to 20.  
  
 
|-
 
|-
| 04.54
+
| 04:54
 
| Next we shall look at implementing the '''each''' loop for a non-inclusive range.  
 
| Next we shall look at implementing the '''each''' loop for a non-inclusive range.  
  
 
|-
 
|-
| 05.00
+
| 05:00
 
|Continue to type this part of the code.  
 
|Continue to type this part of the code.  
  
 
|-
 
|-
| 05.04
+
| 05:04
 
| Non-inclusive means it will not include the last element in the collection of objects.  
 
| Non-inclusive means it will not include the last element in the collection of objects.  
  
 
|-
 
|-
| 05.10
+
| 05:10
 
| Here an '''each''' loop is implemented for a non-inclusive range of numbers 1 to 20.  
 
| Here an '''each''' loop is implemented for a non-inclusive range of numbers 1 to 20.  
  
  
 
|-
 
|-
| 05.16
+
| 05:16
 
| You will notice shortly that the number 20 will not be printed in the output.  
 
| You will notice shortly that the number 20 will not be printed in the output.  
  
 
|-
 
|-
| 05.20
+
| 05:20
 
| The last digit does not get included when you have 3 dots between numbers.  
 
| The last digit does not get included when you have 3 dots between numbers.  
  
 
|-
 
|-
| 05.25
+
| 05:25
 
|Now open the '''terminal''' and type '''ruby space each hyphen loop dot rb'''
 
|Now open the '''terminal''' and type '''ruby space each hyphen loop dot rb'''
  
 
|-
 
|-
| 05.34
+
| 05:34
 
| and see the output.  
 
| and see the output.  
  
 
|-
 
|-
| 05.39
+
| 05:39
 
|Now you should be capable enough to write your own '''each''' loop.  
 
|Now you should be capable enough to write your own '''each''' loop.  
  
 
|-
 
|-
| 05.44
+
| 05:44
 
|How would we determine which looping construct to choose?  
 
|How would we determine which looping construct to choose?  
  
 
|-
 
|-
| 05.48
+
| 05:48
 
|Let us try to recall the '''for''' loop construct.  
 
|Let us try to recall the '''for''' loop construct.  
 
   
 
   
  
 
|-
 
|-
| 05.53
+
| 05:53
 
|In the first example, we iterated over a set of numbers from 1 to 20 using '''for'''.  
 
|In the first example, we iterated over a set of numbers from 1 to 20 using '''for'''.  
  
 
|-
 
|-
| 05.59
+
| 05:59
 
| Execute ''' ruby space for hyphen loop dot rb''' in your terminal see the output.   
 
| Execute ''' ruby space for hyphen loop dot rb''' in your terminal see the output.   
  
 
|-
 
|-
|06.08
+
|06:08
 
| Now look at the code in '''gedit.'''  
 
| Now look at the code in '''gedit.'''  
  
 
|-
 
|-
| 06.11
+
| 06:11
 
|When you invoke the '''for loop''', '''Ruby''' is actually calling the '''each''' method behind the scenes.  
 
|When you invoke the '''for loop''', '''Ruby''' is actually calling the '''each''' method behind the scenes.  
  
 
|-
 
|-
| 06.16
+
| 06:16
 
|And calling '''each''' or '''for''' will generate the same output.  
 
|And calling '''each''' or '''for''' will generate the same output.  
  
 
|-
 
|-
| 06.21
+
| 06:21
 
|Since the call to '''for''' in turn calls ''' each''', it is preferable to use the '''each''' loop instead.   
 
|Since the call to '''for''' in turn calls ''' each''', it is preferable to use the '''each''' loop instead.   
  
 
|-
 
|-
|  06.28
+
|  06:28
 
| This brings us to the end of this Spoken Tutorial.  
 
| This brings us to the end of this Spoken Tutorial.  
  
  
 
|-
 
|-
| 06.30
+
| 06:30
 
|Let's summarize.  
 
|Let's summarize.  
  
  
 
|-
 
|-
| 06.32
+
| 06:32
 
|In this tutorial we have learnt
 
|In this tutorial we have learnt
  
 
|-
 
|-
|  06.33
+
|  06:33
 
|  Usage of ''' for''' loop  
 
|  Usage of ''' for''' loop  
 
   
 
   
 
|-
 
|-
| 06.35
+
| 06:35
 
|Usage of  '''each''' construct  
 
|Usage of  '''each''' construct  
  
 
|-
 
|-
| 06.38
+
| 06:38
 
|Reasoning behind using '''each''' instead of '''for'''  
 
|Reasoning behind using '''each''' instead of '''for'''  
  
 
|-
 
|-
| 06.41
+
| 06:41
 
|Examples of using the above looping constructs  
 
|Examples of using the above looping constructs  
  
 
|-
 
|-
| 06.45
+
| 06:45
 
| As an assignment  
 
| As an assignment  
  
 
|-
 
|-
| 06.47
+
| 06:47
 
|Write a ruby program using the appropriate loop construct  
 
|Write a ruby program using the appropriate loop construct  
  
 
|-
 
|-
| 06.50
+
| 06:50
 
|to create an output of even numbers from a set of numbers, say 1 to 20
 
|to create an output of even numbers from a set of numbers, say 1 to 20
  
  
 
|-
 
|-
|  06.56
+
|  06:56
 
|  Watch the video available at the following link.
 
|  Watch the video available at the following link.
  
 
|-
 
|-
| 07.00
+
| 07:00
 
|It summarises the Spoken Tutorial project.
 
|It summarises the Spoken Tutorial project.
  
 
|-
 
|-
| 07.03
+
| 07:03
 
|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.  
  
 
|-
 
|-
|  07.08
+
|  07:08
 
|  The Spoken Tutorial Project Team :
 
|  The Spoken Tutorial Project Team :
  
 
|-   
 
|-   
| 07.11
+
| 07:11
 
|Conducts workshops using spoken tutorials  
 
|Conducts workshops using spoken tutorials  
  
 
|-
 
|-
|07.14
+
|07:14
 
|Gives certificates to those who pass an online test  
 
|Gives certificates to those who pass an online test  
  
 
|-
 
|-
| 07.18
+
| 07:18
 
|For more details, please write to contact@spoken-tutorial.org
 
|For more details, please write to contact@spoken-tutorial.org
  
 
|-
 
|-
|  07.23
+
|  07:23
 
|  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.
  
 
|-
 
|-
| 07.26
+
| 07:26
 
|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.
  
 
|-
 
|-
| 07.33
+
| 07:33
 
|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
  
 
|-
 
|-
| 07.41
+
| 07:41
 
| This is Anjana Nair signing off. Thank you
 
| This is Anjana Nair signing off. Thank you
  
 
|}
 
|}

Revision as of 15:52, 10 July 2014


Time Narration
00:01 Welcome to the tutorial on for and each Loops in Ruby.
00:05 In this tutorial we will learn
00:07 Meaning of the term “loop”
00:08 The different kinds of loops in Ruby
00:11 Usage of “for” loop and
00:12 Usage of “each” looping construct
00:14 Here we are using
00:16 Ubuntu version 12.04
00:19 Ruby 1.9.3
00:22 To follow this tutorial, you must have Internet Connection.


00:25 You must also have knowledge of Linux commands, Terminal and Text-editor.


00:30 If not, for relevant tutorials, please visit our website.
00:34 Now let me explain what is referred to as a “loop” in Ruby.
00:38 A loop is a command or set of commands that are executed a fixed number of times.
00:44 Ruby has the following main looping statements.
00:47 for
00:48 each
00:49 while
00:49 until
00:50 In this tutorial we will learn how to use the for and each looping constructs.
00:55 Before we begin, please create the following folders in your home directory,
01:02 ttt, ruby hyphen tutorial, looping hyphen statements.
01:07 Please create the sub folders as mentioned there
01:11 Now we have created the requisite folders.
01:13 Let's move ahead.
01:15 The syntax of the “for” loop in Ruby is as follows:


01:19 for “variable” in “a collection of objects”


01:22 ruby code
01:23 end
01:25 Let us try to understand it with an example.
01:28 Create a new file in gedit as shown in the basic level Ruby tutorials.
01:32 And name it “for hyphen loop dot rb”


01:36 I already have a working example of the “for” loop.
01:39 You can type the code as we go through this example.
01:44 I have declared a “for” loop in this example.
01:47 We have a set of numbers 1 to 20.
01:50 We declare a variable called “i” within the “for” loop.


01:55 The variable “i” gets initialized to the first element in the set of numbers 1 to 20.
02:00 The “for” loop declaration causes the code to iterate over each element in the set 1 to 20.
02:07 The “puts” method declared within the “for” loop is responsible for generating the output.


02:14 Now open the terminal and type
02:17 ruby space for hyphen loop dot rb and see the output
02:22 The output will be an array of numbers 1 to 20.
02:26 In this example, we declared a “for” loop for an inclusive range.
02:31 It included all numbers from 1 to 20.
02:35 Next, we shall look at implementing the “for” loop for a non-inclusive range.
02:41 Continue to type the next part of the code.
02:44 Non-inclusive means it will not include the last element in the collection of objects.
02:49 Here “for” loop is implemented for a non-inclusive range of numbers 1 to 20.
02:55 You will notice shortly that the number 20 will not be printed in the output.
02:59 The last digit does not get included when you have 3 dots between numbers.
03:04 Now open the terminal and type ruby space for hyphen loop dot rb
03:13 and see the output.
03:17 The output will still be an array of numbers but will not include the number 20.


03:22 Now, you should be capable enough to write your own “for” loop.
03:27 The syntax of the “each” loop in Ruby is as follows:
03:31 “a collection of objects” dot each do item
03:36 ruby code end
03:38 Let us try to understand it with an example.


03:42 Create a new file in gedit as shown in the basic level Ruby tutorials.
03:46 And name it each hyphen loop dot rb
03:50 I already have a working example of the each loop.
03:53 You can type the code as we go through this example.
03:58 I have declared an each loop in this example.
04:03 We have a set of numbers 1 to 20.
04:06 We declare a variable called “i” within the each loop.


04:11 The “i” variable gets initialized to the first element in the set of numbers 1 to 20.


04:17 The each loop declaration causes the code to iterate over each element in the set 1 to 20.
04:23 The puts method declared within the each is responsible for generating the output.
04:30 Now open the terminal and type ruby space each hyphen loop dot rb
04:39 and see the output.


04:43 The output will be an array of numbers 1 to 20.


04:46 In the above example we declared an each loop for an inclusive range.


04:51 It included all numbers from 1 to 20.
04:54 Next we shall look at implementing the each loop for a non-inclusive range.
05:00 Continue to type this part of the code.
05:04 Non-inclusive means it will not include the last element in the collection of objects.
05:10 Here an each loop is implemented for a non-inclusive range of numbers 1 to 20.


05:16 You will notice shortly that the number 20 will not be printed in the output.
05:20 The last digit does not get included when you have 3 dots between numbers.
05:25 Now open the terminal and type ruby space each hyphen loop dot rb
05:34 and see the output.
05:39 Now you should be capable enough to write your own each loop.
05:44 How would we determine which looping construct to choose?
05:48 Let us try to recall the for loop construct.


05:53 In the first example, we iterated over a set of numbers from 1 to 20 using for.
05:59 Execute ruby space for hyphen loop dot rb in your terminal see the output.
06:08 Now look at the code in gedit.
06:11 When you invoke the for loop, Ruby is actually calling the each method behind the scenes.
06:16 And calling each or for will generate the same output.
06:21 Since the call to for in turn calls each, it is preferable to use the each loop instead.
06:28 This brings us to the end of this Spoken Tutorial.


06:30 Let's summarize.


06:32 In this tutorial we have learnt
06:33 Usage of for loop
06:35 Usage of each construct
06:38 Reasoning behind using each instead of for
06:41 Examples of using the above looping constructs
06:45 As an assignment
06:47 Write a ruby program using the appropriate loop construct
06:50 to create an output of even numbers from a set of numbers, say 1 to 20


06:56 Watch the video available at the following link.
07:00 It summarises the Spoken Tutorial project.
07:03 If you do not have good bandwidth, you can download and watch it.
07:08 The Spoken Tutorial Project Team :
07:11 Conducts workshops using spoken tutorials
07:14 Gives certificates to those who pass an online test
07:18 For more details, please write to contact@spoken-tutorial.org
07:23 Spoken Tutorial Project is a part of the Talk to a Teacher project.
07:26 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
07:33 More information on this Mission is available at spoken hyphen tutorial dot org slash NMEICT hyphen Intro
07:41 This is Anjana Nair signing off. Thank you

Contributors and Content Editors

Jyotisolanki, PoojaMoolya, Pratik kamble, Sandhya.np14