Difference between revisions of "Ruby/C3/for-and-each-Looping-Statements/English-timed"
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− | || ''Time''' | + | || '''Time''' |
|| '''Narration''' | || '''Narration''' | ||
|- | |- | ||
− | | 00 | + | | 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 | + | | 00:05 |
| In this tutorial we will learn | | In this tutorial we will learn | ||
|- | |- | ||
− | | 00 | + | | 00:07 |
| Meaning of the term ''' “loop” ''' | | Meaning of the term ''' “loop” ''' | ||
|- | |- | ||
− | | 00 | + | | 00:08 |
|The different kinds of loops in '''Ruby ''' | |The different kinds of loops in '''Ruby ''' | ||
|- | |- | ||
− | | 00 | + | | 00:11 |
| Usage of ''' “for” ''' loop and | | Usage of ''' “for” ''' loop and | ||
|- | |- | ||
− | | 00 | + | | 00:12 |
|Usage of ''' “each” ''' looping construct | |Usage of ''' “each” ''' looping construct | ||
|- | |- | ||
− | | 00 | + | | 00:14 |
|Here we are using | |Here we are using | ||
|- | |- | ||
− | | 00 | + | | 00:16 |
| ''' Ubuntu''' version 12.04 | | ''' Ubuntu''' version 12.04 | ||
|- | |- | ||
− | | 00 | + | | 00:19 |
|''' Ruby '''1.9.3 | |''' Ruby '''1.9.3 | ||
|- | |- | ||
− | | 00 | + | | 00:22 |
|To follow this tutorial, you must have ''' Internet''' Connection. | |To follow this tutorial, you must have ''' Internet''' Connection. | ||
− | |||
|- | |- | ||
− | | 00 | + | | 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.''' | ||
− | |||
|- | |- | ||
− | | 00 | + | | 00:30 |
|If not, for relevant tutorials, please visit our website. | |If not, for relevant tutorials, please visit our website. | ||
|- | |- | ||
− | | 00 | + | | 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 | + | | 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 | + | | 00:44 |
|''' Ruby''' has the following main looping statements. | |''' Ruby''' has the following main looping statements. | ||
|- | |- | ||
− | | 00 | + | | 00:47 |
|'''for''' | |'''for''' | ||
|- | |- | ||
− | | 00 | + | | 00:48 |
| '''each ''' | | '''each ''' | ||
|- | |- | ||
− | | 00 | + | | 00:49 |
|''' while''' | |''' while''' | ||
|- | |- | ||
− | | 00 | + | | 00:49 |
| '''until''' | | '''until''' | ||
|- | |- | ||
− | | 00 | + | | 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 | + | | 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 | + | | 01:02 |
| ttt, ruby hyphen tutorial, looping hyphen statements. | | ttt, ruby hyphen tutorial, looping hyphen statements. | ||
|- | |- | ||
− | | 01 | + | | 01:07 |
| Please create the sub folders as mentioned there | | Please create the sub folders as mentioned there | ||
|- | |- | ||
− | | 01 | + | | 01:11 |
|Now we have created the requisite folders. | |Now we have created the requisite folders. | ||
|- | |- | ||
− | | 01 | + | | 01:13 |
|Let's move ahead. | |Let's move ahead. | ||
|- | |- | ||
− | | 01 | + | | 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 | + | | 01:19 |
| ''' for “variable” in “a collection of objects” ''' | | ''' for “variable” in “a collection of objects” ''' | ||
− | |||
|- | |- | ||
− | | 01 | + | | 01:22 |
|''' ruby code ''' | |''' ruby code ''' | ||
|- | |- | ||
− | | 01 | + | | 01:23 |
| ''' end ''' | | ''' end ''' | ||
|- | |- | ||
− | | 01 | + | | 01:25 |
| Let us try to understand it with an example. | | Let us try to understand it with an example. | ||
|- | |- | ||
− | | 01 | + | | 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 | + | | 01:32 |
|And name it ''' “for hyphen loop dot rb” ''' | |And name it ''' “for hyphen loop dot rb” ''' | ||
|- | |- | ||
− | | 01 | + | | 01:36 |
|I already have a working example of the ''' “for” ''' loop. | |I already have a working example of the ''' “for” ''' loop. | ||
|- | |- | ||
− | | 01 | + | | 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 | + | | 01:44 |
| I have declared a ''' “for” ''' loop in this example. | | I have declared a ''' “for” ''' loop in this example. | ||
|- | |- | ||
− | | 01 | + | | 01:47 |
| We have a set of numbers 1 to 20. | | We have a set of numbers 1 to 20. | ||
|- | |- | ||
− | | 01 | + | | 01:50 |
| We declare a variable called “i” within the ''' “for” ''' loop. | | We declare a variable called “i” within the ''' “for” ''' loop. | ||
|- | |- | ||
− | | 01 | + | | 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 | + | | 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 | + | | 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 | + | | 02:14 |
|Now open the ''' terminal''' and type | |Now open the ''' terminal''' and type | ||
|- | |- | ||
− | | 02 | + | | 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 | + | | 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 | + | | 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 | + | | 02:31 |
| It included all numbers from 1 to 20. | | It included all numbers from 1 to 20. | ||
|- | |- | ||
− | | 02 | + | | 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 | + | | 02:41 |
|Continue to type the next part of the code. | |Continue to type the next part of the code. | ||
|- | |- | ||
− | | 02 | + | | 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 | + | | 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 | + | | 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 | + | | 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 | + | | 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 | + | | 03:13 |
|and see the output. | |and see the output. | ||
|- | |- | ||
− | | 03 | + | | 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 | + | | 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 | + | | 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 | + | | 03:31 |
| ''' “a collection of objects” dot each do item ''' | | ''' “a collection of objects” dot each do item ''' | ||
|- | |- | ||
− | | 03 | + | | 03:36 |
| ''' ruby code end''' | | ''' ruby code end''' | ||
|- | |- | ||
− | | 03 | + | | 03:38 |
|Let us try to understand it with an example. | |Let us try to understand it with an example. | ||
|- | |- | ||
− | | 03 | + | | 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 | + | | 03:46 |
|And name it '''each hyphen loop dot rb''' | |And name it '''each hyphen loop dot rb''' | ||
|- | |- | ||
− | | 03 | + | | 03:50 |
|I already have a working example of the '''each''' loop. | |I already have a working example of the '''each''' loop. | ||
|- | |- | ||
− | | 03 | + | | 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 | + | | 03:58 |
|I have declared an '''each''' loop in this example. | |I have declared an '''each''' loop in this example. | ||
|- | |- | ||
− | | 04 | + | | 04:03 |
| We have a set of numbers 1 to 20. | | We have a set of numbers 1 to 20. | ||
|- | |- | ||
− | | 04 | + | | 04:06 |
|We declare a variable called “i” within the '''each''' loop. | |We declare a variable called “i” within the '''each''' loop. | ||
− | |||
|- | |- | ||
− | | 04 | + | | 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 | + | | 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 | + | | 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 | + | | 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 | + | | 04:39 |
| and see the output. | | and see the output. | ||
− | |||
|- | |- | ||
− | | 04 | + | | 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 | + | | 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 | + | | 04:51 |
|It included all numbers from 1 to 20. | |It included all numbers from 1 to 20. | ||
|- | |- | ||
− | | 04 | + | | 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 | + | | 05:00 |
|Continue to type this part of the code. | |Continue to type this part of the code. | ||
|- | |- | ||
− | | 05 | + | | 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 | + | | 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 | + | | 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 | + | | 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 | + | | 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 | + | | 05:34 |
| and see the output. | | and see the output. | ||
|- | |- | ||
− | | 05 | + | | 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 | + | | 05:44 |
|How would we determine which looping construct to choose? | |How would we determine which looping construct to choose? | ||
|- | |- | ||
− | | 05 | + | | 05:48 |
|Let us try to recall the '''for''' loop construct. | |Let us try to recall the '''for''' loop construct. | ||
|- | |- | ||
− | | 05 | + | | 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 | + | | 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 | + | |06:08 |
| Now look at the code in '''gedit.''' | | Now look at the code in '''gedit.''' | ||
|- | |- | ||
− | | 06 | + | | 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 | + | | 06:16 |
|And calling '''each''' or '''for''' will generate the same output. | |And calling '''each''' or '''for''' will generate the same output. | ||
|- | |- | ||
− | | 06 | + | | 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 | + | | 06:28 |
| This brings us to the end of this Spoken Tutorial. | | This brings us to the end of this Spoken Tutorial. | ||
− | |||
|- | |- | ||
− | | 06 | + | | 06:30 |
|Let's summarize. | |Let's summarize. | ||
− | |||
|- | |- | ||
− | | 06 | + | | 06:32 |
|In this tutorial we have learnt | |In this tutorial we have learnt | ||
|- | |- | ||
− | | 06 | + | | 06:33 |
| Usage of ''' for''' loop | | Usage of ''' for''' loop | ||
|- | |- | ||
− | | 06 | + | | 06:35 |
|Usage of '''each''' construct | |Usage of '''each''' construct | ||
|- | |- | ||
− | | 06 | + | | 06:38 |
|Reasoning behind using '''each''' instead of '''for''' | |Reasoning behind using '''each''' instead of '''for''' | ||
|- | |- | ||
− | | 06 | + | | 06:41 |
|Examples of using the above looping constructs | |Examples of using the above looping constructs | ||
|- | |- | ||
− | | 06 | + | | 06:45 |
| As an assignment | | As an assignment | ||
|- | |- | ||
− | | 06 | + | | 06:47 |
|Write a ruby program using the appropriate loop construct | |Write a ruby program using the appropriate loop construct | ||
|- | |- | ||
− | | 06 | + | | 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 | + | | 06:56 |
| Watch the video available at the following link. | | Watch the video available at the following link. | ||
|- | |- | ||
− | | 07 | + | | 07:00 |
|It summarises the Spoken Tutorial project. | |It summarises the Spoken Tutorial project. | ||
|- | |- | ||
− | | 07 | + | | 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 | + | | 07:08 |
| The Spoken Tutorial Project Team : | | The Spoken Tutorial Project Team : | ||
|- | |- | ||
− | | 07 | + | | 07:11 |
|Conducts workshops using spoken tutorials | |Conducts workshops using spoken tutorials | ||
|- | |- | ||
− | |07 | + | |07:14 |
|Gives certificates to those who pass an online test | |Gives certificates to those who pass an online test | ||
|- | |- | ||
− | | 07 | + | | 07:18 |
|For more details, please write to contact@spoken-tutorial.org | |For more details, please write to contact@spoken-tutorial.org | ||
|- | |- | ||
− | | 07 | + | | 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 | + | | 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 | + | | 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 | + | | 07:41 |
| This is Anjana Nair signing off. Thank you | | This is Anjana Nair signing off. Thank you | ||
|} | |} |
Revision as of 14:19, 28 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 |