Java/C2/Introduction-to-Array/English-timed - Revision history

PoojaMoolya at 13:59, 20 February 2017

2017-02-20T13:59:24Z

Sandhya.np14 at 17:25, 6 April 2015

2015-04-06T17:25:00Z

Sandhya.np14 at 17:08, 28 March 2015

2015-03-28T17:08:29Z

Sandhya.np14 at 17:06, 28 March 2015

2015-03-28T17:06:28Z

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Jyotisolanki at 06:44, 9 October 2013

2013-10-09T06:44:52Z

Sneha: Created page with ' {| border = 1 |'''Time''' |'''Narration''' |- | 00:02 | Welcome to the spoken tutorial on '''Introduction to Arrays'''. |- | 00:07 | In this tutorial, you will learn …'

2013-05-29T06:26:37Z

Created page with ' {| border = 1 |'''Time''' |'''Narration''' |- | 00:02 | Welcome to the spoken tutorial on '''Introduction to Arrays'''. |- | 00:07 | In this tutorial, you will learn …'

New page

{| border = 1

|'''Time'''

|'''Narration'''
|-
| 00:02
| Welcome to the spoken tutorial on '''Introduction to Arrays'''.

|-
| 00:07
| In this tutorial, you will learn how to '''create arrays''' and access elements in '''arrays'''.

|-
| 00:14
| For this tutorial we are using

* '''Ubuntu 11.10'''
* '''JDK 1.6''' and
* '''Eclipse 3.7.0'''

|-
| 00:25
| | For this tutorial, you should have knowledge of '''data types''' and '''for loop in Java.'''

|-
| 00:32
| If not, for relevant tutorial please visit our website which as shown.

|-
| 00:38
| Arrays are a collection of data.

|-
| 00:40
| For example, a list of marks, a list of names, a list of temperatures, a list of rainfall,

|-
| 00:47
| Each item has an index based on its position.

|-
| 00:52
| The index of the first element is 0.

|-
| 00:55
| The index of the second element is 1 and so on.

|-
| 00:59
| Let us now see how to store this data.

|-
| 01:03
| So switch to '''Eclipse.'''

|-
| 01:06
| A '''class''' named '''ArraysDemo '''has already been created.

|-
| 01:11
| Within the main method, let us add the rainfall data.

|-
| 01:16
| So Inside main function, type

|-
| 01:18
| '''int rainfall '''''open and close brackets equal to''''' '''''within curly brackets type''''' 25, 31, 29, 13, 27, 35, 12 ''''' and finally a semicolon.''

|-
| 01:53
| Note the square braces after the '''variable '''name''' rainfall'''.

|-
| 01:58
| This declares '''rainfall''' as an '''array''' of '''integers'''.

|-
| 02:03
| The braces are used to specify the elements of the array.

|-
| 02:09
| let us now access data.

|-
| 02:12
| So on the Next line, type

|-
| 02:14
| '''System '''''dot '''''out '''''dot'' '''println ''' ''' rainfall ''' in square brackets type 2

|-
| 02:28
| We are printing the element with the index number 2.

|-
| 02:32
| In other words, the third element in the array i.e.29.

|-
| 02:38
| Let us save run the program

|-
| 02:43
|As we can see, the output is the third element,i.e '''29'''.

|-
| 02:49
| Now let us type 0 in place of 2

|-
| 02:56
| Save and run the program

|-
| 03:00
| As we can see, the output is the first value i.e 25

|-
| 03:07
| Now let us modify the value of the first item

|-
| 03:13
| So type '''rainfall [0] = 11; '''

|-
| 03:27
| Now let us see its value. So save and run the program

|-
| 03:34
| As we can see, the value has been changed to 11.

|-
| 03:40
| Now what if we know only the size of the array and do not know the values.
|-
| 03:45
| Let us see how to create such array.

|-
| 03:49
| Remove everything in main function and type
|-
| 03:57
| '''int squares [] = new int [10]; '''
|-
| 04:19
| This statement creates an array of integers having 10 elements. The name of the array is '''squares'''.
|-
| 04:30
| Now let us add some values to it

|-
| 04:33
| So '''Type'''

|-
| 04:35
| '''squares[0] = 1;'''

|-
| 04:43
| Next line'''squares[1] = 4;'''

|-
| 04:53
| Next line'''squares[2] = 9;'''

|-
| 05:04
| '''squares[3] = 16;'''

|-
| 05:15
| So We have entered the squares of first four numbers.
|-
| 05:20
| Now what about the other elements of the array. Let us see what they contain.

|-
| 05:26
| So We shall print the sixth value in the array.

|-
| 05:30
| Type '''System.out.println(squares [5]); '''

|-
| 05:56
| Save and run the program.We see that the value is zero.

|-
| 06:05
| This is because when we create an array of integers, all the values are initialized to 0.

|-
| 06:11
| Similarly an array of floats will have all its values initialized to 0.0.

|-
| 06:18
| It would be a long process if we have to type each value into the array. Instead, let us use a for loop.

|-
| 06:28
| So '''Type'''

'''int n, x ; '''

'''for(x = 4; x < 10; x = x + 1){'''

'''n = x + 1;'''

'''squares [x] = n * n;'''

'''} '''

|-
| 07:25
|So We iterate over numbers from 4 to 9 and set the corresponding element in the array.

|-
| 07:36
| Now let us see the output.

|-
| 07:38
| | As we can see, we are printing the value of sixth element in array SoSave and run.
|-
| 07:52
| We see the sixth element is now square of 6, which is 36.

|-
| 07:57
| In fact now we can set all the values inside the for loop.

|-
| 08:03
| Remove the lines that set the values manually and change '''4''' to '''0'''

|-
| 08:14
| This way all the elements from index 0 to 9 are set to the corresponding squares.

|-
| 08:21
| We shall now see the value of the third element.

|-
| 08:25
| So change '''5 '''to '''2'''

|-
| 08:30
| Save and run

|-
| 08:35
| As we can see, the value of the third element has been set in the loop and it is 9.

|-
| 08:42
| This way, arrays can be created and used.

|-
| 08:50
| We have come to the end of this tutorial.

|-
| 08:53
| In this tutorial we have learnt
|-
| 08:55
| TO declare and initialize the array ,
|-
| 08:58
| And access element in an array
|-
| 09:01
| The assignment for this tutorial is,

|-
| 09:04
| Given an array of integers, find the sum of all the elements in the array.

|-
| 09:10
| To know more about the '''Spoken Tutorial''' project,
|-
| 09:13
| watch the video available at the following link.
|-
| 09:19
| It summarises the project.If you do not have good bandwidth, you can download and watch it.

|-
| 09:26
| The Spoken Tutorial Project Team. Conducts workshops using '''spoken tutorials''' and gives certificates for 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.
|-
| 09:50
| '''More information on this Mission is available at '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''

|-
| 09:57
| This script has been contributed by '''TalentSprint'''.

This is Prathamesh Salunke signing off. Thanks for joining.

|}

@@ Line 216: / Line 216: @@
 | 06:28
 |  So, type:
 '''int n, x ;'''
 '''for(x = 4; x  < 10; x = x + 1){'''
 '''n = x + 1;'''
 '''squares[x] = n * n;'''
 '''}'''
@@ Line 243: / Line 247: @@
 |-
 |  08:03
-| Remove the lines that set the values manually and change '''4''' to '''0'''
+| Remove the lines that set the values manually and change '''4''' to '''0'''.
 |-

@@ Line 223: / Line 223: @@
 |-
 | 05:30
-|  Type '''System.out.println(squares [5]); '''
+|  Type '''System S capital.out.println(squares [5]); '''

@@ Line 1: / Line 1: @@
 {| border = 1
 |'''Time'''
 |-
 |  00:02
@@ Line 18: / Line 14: @@
 |  00:14
 |   For this tutorial, we are using:
-* '''Ubuntu 11.10'''
+'''Ubuntu 11.10'''
-* '''JDK 1.6''' and
+'''JDK 1.6''' and
-* '''Eclipse 3.7.0'''
+'''Eclipse 3.7.0'''
 |-
 | 00:25
-| | For this tutorial, you should have knowledge of '''data types''' and '''for loop''' in Java.
+| For this tutorial, you should have knowledge of '''data types''' and '''for loop''' in Java.
 |-
@@ Line 203: / Line 199: @@
 |-
 | 06:05
-  | This is because when we create an '''array''' of integers, all the values are initialized to 0.
+| This is because when we create an '''array''' of integers, all the values are initialized to 0.
 |-
@@ Line 236: / Line 232: @@
 |-
 | 07:38
-|  | As we can see, we are printing the  value of sixth element in  '''array'''. So, '''Save''' and '''run'''.
+| As we can see, we are printing the  value of sixth element in  '''array'''. So, '''Save''' and '''run'''.
 |-
 | 07:52
@@ Line 282: / Line 278: @@
 |-
 | 08:55
-|* To declare and initialize an '''array'''.
+|To declare and initialize an '''array'''.
 |-
 | 08:58
-|* And access an element in an '''array'''.
+|And access an element in an '''array'''.
 |-
 |   09:01

@@ Line 13: / Line 13: @@
 |-
 |  00:07
-|   In this tutorial, you will learn how  to create '''arrays''' and  access elements in '''array'''s.
+|   In this tutorial, you will learn how  to create '''array'''s and  access elements in '''array'''s.
 |-
@@ Line 72: / Line 72: @@
 |-
 | 01:18
-| '''int rainfall''' open  and 	close   brackets equal to within curly brackets type '''25, 31, 29, 13, 27, 35, 12''' and finally a semicolon.
+| '''int rainfall''' open  and 	close square  brackets equal to within curly brackets type '''25, 31, 29, 13, 27, 35, 12''' and finally the semicolon.
 |-
 | 01:53
-| Note the square braces after the '''variable''' name '''rainfall'''.
+| Note that the square braces after the '''variable''' name '''rainfall'''.
 |-
@@ Line 108: / Line 108: @@
 |-
 | 02:38
-| Let us '''save''', '''run''' the program.
+| Let us '''save''' and '''run''' the program.
 |-
@@ Line 195: / Line 195: @@
 |-
 | 05:30
-|  Type: '''System''' S capital '''.out.println(squares [5]);'''
+|  Type: '''System''' S capital '''.out.println(squares[5]);'''
 |-
@@ Line 279: / Line 279: @@
 |-
 | 08:53
-| In this tutorial we have learnt:
+| In this tutorial, we have learnt:
 |-
 | 08:55
-|* TO declare and initialize the '''array'''.
+|* To declare and initialize an '''array'''.
 |-
 | 08:58
@@ Line 306: / Line 306: @@
 |-
 |  09:26
-|  The Spoken Tutorial project team: Conducts workshops using spoken tutorials and gives certificates for those who pass an online test.
+|  The Spoken Tutorial project team: Conducts workshops using spoken tutorials and gives certificates to those who pass an online test.
 |-
 | 09:34