Ruby/C3/Object-Oriented-Programming-Methods/English-timed - Revision history

PoojaMoolya at 07:10, 10 March 2017

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Sandhya.np14 at 09:35, 26 March 2016

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Sandhya.np14 at 10:28, 3 February 2016

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Sandhya.np14 at 12:35, 2 February 2016

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Sandhya.np14 at 07:43, 2 February 2016

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Sandhya.np14 at 04:38, 17 November 2015

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Sandhya.np14 at 03:04, 30 October 2015

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PoojaMoolya at 05:15, 10 March 2015

2015-03-10T05:15:00Z

PoojaMoolya: Created page with " {| Border = 1 | | '''Time''' | | '''Narration''' |- | | 00:01 | | Welcome to this spoken tutorial on '''Object Oriented Programming – Methods '''in '''Ruby'''. |- | | 0..."

2015-03-10T05:14:09Z

Created page with " {| Border = 1 | | '''Time''' | | '''Narration''' |- | | 00:01 | | Welcome to this spoken tutorial on '''Object Oriented Programming – Methods '''in '''Ruby'''. |- | | 0..."

New page

{| Border = 1
| | '''Time'''
| | '''Narration'''

|-
| | 00:01
| | Welcome to this spoken tutorial on '''Object Oriented Programming – Methods '''in '''Ruby'''.

|-
| | 00:07
| | In this tutorial we will learn to use:

|-
| | 00:09
| | '''instance methods'''

|-
| | 00:11
| |'''class methods'''

|-
| | 00:14
| | '''accessor methods'''

|-
| | 00:15
| | Here we are using '''Ubuntu '''version 12.04

|-
| | 00:19
| | '''Ruby'''1.9.3

|-
| | 00:22
| | To follow this tutorial, you must have a working '''Internet '''connection.

|-
| | 00:27
| |You must also have knowledge of '''Linux '''commands, '''Terminal '''and '''Text-editor.'''

|-
| | 00:31
| |If not, for relevant tutorials, please visit our website.

|-
| | 00:36
| | Before we begin, recall that we had created “'''ttt'''” directory earlier.

|-
| | 00:41
| | Let's go to that directory.

|-
| | 00:44
| | Then to '''ruby-tutorial.'''

|-
| | 00:47
| |Create a directory named '''oop-methods''' and cd into it.

|-
| | 00:54
| | What are '''Instance methods'''?

|-
| | 00:56
| |'''Instance methods '''are those '''methods '''that are available to all '''instances '''of the '''class.'''

|-
| | 01:03
| |Earlier we had studied how to create '''objects '''or '''instances ''' of a''' class'''.

|-
| | 01:09
| | Create a new file in '''gedit '''as shown in the basic level '''Ruby '''tutorials.

|-
| | 01:14
| |Name it '''instance_methods.rb'''

|-
| | 01:19
| | I have a working example of the implementing '''instance methods'''.

|-
| | 01:24
| |You can pause the tutorial, and type the code as we go through it.

|-
| | 01:29
| | I have defined a '''class '''named '''Product''' in this example.

|-
| | 01:33
| | I have called an '''initialize method '''to initialize the '''instance variables "name"''' and '''"price"'''.

|-
| | 01:41
| | I have also defined '''instance methods '''named '''"name"''' and '''"price"'''.

|-
| | 01:47
| |Each of them return '''instance variables "name"''' and '''"price"''' respectively.

|-
| | 01:54
| | '''Instance methods '''are defined just like normal '''methods'''.

|-
| | 01:58
| |Earlier we had studied how to create '''methods '''in '''Ruby'''.

|-
| | 02:02
| |Shortly, we will see how these '''methods '''will be available to all '''instances.'''

|-
| | 02:07
| | Now let us implement the logic we have.

|-
| | 02:11
| | Here, I have initialized a '''Product''' '''object '''and named it as '''product_object_1'''.

|-
| | 02:18
| |I have initialized it with a '''name value''' and a '''price value'''.

|-
| | 02:24
| | The '''initializer block''' passes the values to the '''instance variables @name''' and '''@price'''.

|-
| | 02:31
| | Now this '''product instance '''or '''object''' can use the''' instance methods name''' and '''price'''.

|-
| | 02:37
| |On invoking these '''methods,''' we get the values stored in the '''instance variables'''.

|-
| | 02:43
| | Now let us execute this code.

|-
| | 02:46
| |Switch to the '''terminal''' and type: '''ruby instance_methods.rb ''' and press '''Enter '''to see the output.

|-
| | 02:56
| | You will see that it will print the values you initialized the '''object''' with.

|-
| | 03:02
| |Namely, '''laptop '''and '''35,000'''.

|-
| | 03:07
| | Next, initialize another '''instance''' or '''object'''.

|-
| | 03:12
| |Let us name this object '''product_object_2'''.

|-
| | 03:18
| |This time, let us give a different set of values for '''name''' and '''price'''.

|-
| | 03:23
| | Now let us call the '''instance methods "name"''' and '''"price"'''” for this '''object.'''

|-
| | 03:35
| | Next let us switch back to the '''terminal''' and execute the code like before.

|-
| | 03:41
| | You will notice that it executes successfully and it prints out the new values.

|-
| | 03:48
| |This proves that '''instance methods''' are available to all '''objects''' of the '''class Product'''.

|-
| | 03:55
| | You should now be able to write your own '''instance methods.'''

|-
| | 03:59
| | Next, let us look at what '''class methods '''are.

|-
| | 04:04
| | '''Class methods''' are '''methods '''available only to the '''class.'''

|-
| | 04:09
| |These '''methods '''are not available to '''instances''' of the '''class.'''

|-
| | 04:14
| |There are different ways you can define '''class methods'''.

|-
| | 04:16
| | Let us look at an example.

|-
| | 04:18
| | Create a new file in '''gedit '''as shown in the basic level '''Ruby '''tutorials.

|-
| | 04:24
| |Name it '''class_methods.rb'''

|-
| | 04:28
| | I have a working example of '''class methods'''.

|-
| | 04:32
| |You can pause the tutorial, and type the code as we go through it.

|-
| | 04:36
| | I have defined a '''Product class''' like before.

|-
| | 04:40
| | I have also called an '''initializer''' like before.

|-
| | 04:44
| |However, this time I have added an extra '''argument''' called '''description'''.

|-
| | 04:48
| |I am also using '''class variables''' to hold the values unlike '''instance variables''', earlier.

|-
| | 04:55
| | This '''class''' will demonstrate to you the 3 different ways one can define '''class methods.'''

|-
| | 05:01
| |Checkout the '''class method '''declaration for '''name'''.

|-
| | 05:06
| |Here it is defined using the '''class name "Product"'''.

|-
| |05:10
| | Then, checkout the second '''class methods''' declaration.

|-
| | 05:14
| |Here I have used the '''"self" keyword'''.

|-
| | 05:18
| | Next, checkout the third way you can define '''class methods'''.

|-
| | 05:23
| | Now let us implement these '''class methods'''.

|-
| | 05:27
| | Let us first initialize an '''object''' of '''Product,''' like before.

|-
| | 05:32
| |This time we are also giving a value for the '''description'''.

|-
| | 05:37
| | Now let us invoke the '''class methods''' as shown here.

|-
| | 05:42
| | Now let us execute the code and inspect the output.

|-
| | 05:47
| | Switch to the '''terminal''' and execute the code like before.

|-
| | 05:54
| | You will notice that it will print the values for '''name, price '''and''' description.'''

|-
| | 05:59
| | Now you should be able to write your own '''class methods'''.

|-
| | 06:03
| | Next we shall see what '''accessor methods''' are.

|-
| | 06:07
| | '''Ruby''' uses '''accessor methods''' to access data defined within '''classes'''.

|-
| | 06:13
| |'''Accessor methods''' comprise of '''setter methods''' and '''getter methods'''.

|-
| | 06:18
| |'''Setter methods''' set the values.

|-
| | 06:22
| |'''Getter methods''' get those values.

|-
| | 06:24
| |'''Ruby''' uses the word '''attr_accessor''' to declare these '''methods'''.

|-
| | 06:31
| | Let us look at an example of '''accessor methods'''.

|-
| | 06:35
| | Create a new file in '''gedit '''as shown in the basic level '''Ruby '''tutorials.

|-
| | 06:39
| |Name it '''accessor_methods.rb'''

|-
| | 06:43
| | I have a working example of the implementing '''accessor methods'''.

|-
| | 06:47
| |You can pause the tutorial, and type the code as we go through it.

|-
| | 06:52
| | I have defined a '''class''' named '''Product,''' in this example.

|-
| | 06:56
| |I have declared '''attr_accessor '''for''' name and price.'''

|-
| | 07:01
| |That is all that is required to use these types of '''methods'''.

|-
| | 07:05
| | Now let us put it to action.

|-
| | 07:07
| |I have initialized a '''Product object'''.

|-
| | 07:10
| | Then, I have set the '''name''' and '''price''' of the '''product object'''.

|-
| | 07:14
| |This is possible because the '''attr_declaration,''' by default, creates '''methods''' for setting values.

|-
| | 07:22
| | I have then attempted to print the values using the '''getter methods''' for '''name''' and '''price'''.

|-
| | 07:28
| |These '''getter methods''' were also generated by the declaration of '''attr_accessor'''.

|-
| | 07:35
| | Now let us execute the code like before.

|-
| | 07:40
| | You will notice that it prints the values that were set.

|-
| | 07:44
| | By now, you should be able to write your own '''accessor methods'''.

|-
| | 07:50
| | One thing to note is that '''accessor methods''' are, by default,''' instance methods.'''

|-
| | 07:55
| |Thus they can be accessed by different '''instances''' of the '''class Product'''.

|-
| | 08:00
| | In this tutorial we have learnt about: '''instance methods''', '''class methods '''and '''accessor methods'''

|-
| | 08:06
| | As an assignment: Define a '''class''' named '''Temperature'''

|-
| | 08:10
| | Write an '''instance method '''using '''Ruby's accessor method''' syntax.

|-
| | 08:15
| | This '''method''' should calculate the '''Celsius '''for the given '''Fahrenheit.'''

|-
| | 08:20
| | Watch the video available at the following link.

|-
| | 08:23
| |It summarizes the Spoken Tutorial project.

|-
| | 08:26
| |If you do not have good bandwidth, you can download and watch it.

|-
| |08:30
| | The Spoken Tutorial Project Team :

|-
| | 08:31
| |Conducts workshops using spoken tutorials

|-
| | 08:34
| |Gives certificates to those who pass an online test

|-
| | 08:38
| |For more details, please write to contact at spoken hyphen tutorial dot org

|-
| | 08:44
| | Spoken Tutorial Project is a part of the Talk to a Teacher project.

|-
| | 08:48
| |It is supported by the National Mission on Education through ICT, MHRD, Government of India.

|-
| | 08:55
| |More information on this Mission is available at: spoken hyphen tutorial dot org slash NMEICT hyphen Intro.

|-
| | 09:03
| | This is Anjana Nair signing off. Thank you

|}

@@ Line 14: / Line 14: @@
 |-
 | | 00:09
-| |* '''instance methods'''
+| | '''instance methods'''
 |-
 | | 00:11
-| |* '''class methods'''
+| | '''class methods''', '''accessor methods'''.
-−
-|-
-| | 00:14
-| |* '''accessor methods'''.
 |-
 | | 00:15
-| | Here, we are using:
+| | Here, we are using: '''Ubuntu '''version '''12.04'''
-* '''Ubuntu '''version '''12.04'''
 |-
 | | 00:19
-| |* '''Ruby 1.9.3'''
+| | '''Ruby 1.9.3'''
 |-
@@ Line 427: / Line 422: @@
 |-
 | |08:30
-| | The Spoken Tutorial project team:
+| | The Spoken Tutorial project team:  Conducts workshops using spoken tutorials.
-−
-|-
-| | 08:31
-| |* Conducts workshops using spoken tutorials.
 |-
 | | 08:34
-| |* Gives certificates to those who pass an online test.
+| | Gives certificates to those who pass an online test.
 |-
 | | 08:38
-| |For more details, please write to:
+| |For more details, please write to:'''contact at spoken hyphen tutorial dot org'''.
 '''contact at spoken hyphen tutorial dot org'''.
 |-
@@ Line 452: / Line 442: @@
 |-
 | | 08:55
-| |More information on this mission is available at:
+| |More information on this mission is available at: '''spoken hyphen tutorial dot org slash NMEICT hyphen Intro'''.
 '''spoken hyphen tutorial dot org slash NMEICT hyphen Intro'''.
 |-

@@ Line 440: / Line 440: @@
 | | 08:38
 | |For more details, please write to:
-contact at spoken hyphen tutorial dot org.
+'''contact at spoken hyphen tutorial dot org'''.
 |-
@@ Line 453: / Line 453: @@
 | | 08:55
 | |More information on this mission is available at:
-spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
+'''spoken hyphen tutorial dot org slash NMEICT hyphen Intro'''.
 |-

@@ Line 6: / Line 6: @@
 |-
 | | 00:01
-| | Welcome to this '''spoken tutorial''' on '''Object Oriented Programming – Methods '''in '''Ruby'''.
+| | Welcome to this '''spoken tutorial''' on '''Object Oriented Programming – Methods''' in '''Ruby'''.
 |-

@@ Line 303: / Line 303: @@
 |-
 | | 06:07
-| | '''Ruby''' uses '''accessor methods''' to access data defined within '''classes'''.
+| | '''Ruby''' uses '''accessor methods''' to access data, defined within '''classes'''.
 |-
@@ Line 347: / Line 347: @@
 |-
 | | 06:56
-| |I have declared '''attr_accessor '''for''' name''' and '''price.'''
+| |I have declared '''attr_accessor '''for 'name' and 'price'.
 |-
@@ Line 371: / Line 371: @@
 |-
 | | 07:22
-| | I have then attempted to print the values using the '''getter methods''' for '''name''' and '''price'''.
+| | I have then attempted to print the values using the '''getter methods''' for 'name' and 'price'.
 |-

@@ Line 231: / Line 231: @@
 |-
 | | 04:40
-| | I have also called an '''initializer''' like before.
+| | I have also called an '''initializer''', like before.
 |-
@@ Line 335: / Line 335: @@
 |-
 | | 06:43
-| | I have a working example of the implementing '''accessor methods'''.
+| | I have a working example of  implementing '''accessor methods'''.
 |-

@@ Line 123: / Line 123: @@
 |-
 | | 02:11
-| | Here, I have initialized a '''Product''' object and named it as '''product_object_1'''.
+| | Here, I have initialized a '''Product''' object and named it as "product_object_1".
 |-
 | | 02:18
-| |I have initialized it with a '''name value''' and a '''price value'''.
+| |I have initialized it with a '''name''' value and a '''price''' value.
 |-
 | | 02:24
-| | The '''initializer block''' passes the values to the '''instance variables @name''' and '''@price'''.
+| | The '''initializer block''' passes the values to the '''instance variables''' "@name" and "@price".
 |-
@@ Line 155: / Line 155: @@
 |-
 | | 03:02
-| |Namely, '''laptop '''and '''35,000'''.
+| |Namely, "laptop" and "35,000".
 |-

@@ Line 99: / Line 99: @@
 | | 01:41
 | | I have also defined '''instance methods '''named '''"name"''' and '''"price"'''.
 |-
@@ Line 108: / Line 107: @@
 | | 01:54
 | | '''Instance methods '''are defined just like normal '''methods'''.
 |-
 | | 01:58
 | |Earlier we had studied how to create '''methods '''in '''Ruby'''.
 |-
@@ Line 274: / Line 271: @@
 | | 05:27
 | | Let us first initialize an '''object''' of '''Product,''' like before.
 |-