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MULTIDIMENSIONAL ARRAY

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COURSE LEARNING OUTCOMES :

Upon completion of this course, the studentsshould be able to:

1.Describe the features and basic concepts of Javalanguage.

2.Write, compile Java source code and interpret Javabyte code using Java Development Kit (JDK).

3.Implement the key of OOP concepts: classes andobjects, inheritance and polymorphism.

4.Incorporate exception handling in JavaProgramming.

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OBJECTIVES :

Write a program usingmultidimensional array :

Define an arrayDeclare and initialize an array

Pass array to methodsReturn array to methodsWrite program using single array

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arrays with more than one dimension.

is a collection of a number of one-

dimensional arrays placed one below

the other.

Two-dimensional arrays represent

data in terms ofrows and columns. It

has two subscripts.

2D Array

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Representation -2D Array

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Declare & Initialize

Assume that there are 5 students in a

class and each of them study three

different subjects, for example

Mathematics, Physics and Chemistry.

The marks of each student in all three

subjects can be represented in a single

row.

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Representation -1D Array

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Example

int marks_table[][] = new int[5][3];

Syntax

[][] =

New [Row][Column];

Declaration -2D Array

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Representation -2D Array

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Give the value of the followingelements in the 2-D representationseen in Slide 10:

marks_table[0][0]

marks_table[1][1]

marks_table[3][0]

marks_table[4][2]

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Accessing Array Elements

You can use the row and column arrayindex to access the array elements.

For example, if you need to print the valuestored in first row and second column ofthe array marks_table, (i.e. chemistry markof student 2) the code will be :

Example

System.out.println(marks_table[1][2]);

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Enter Data to Array

A nested for loop can be used to enter data

in a 2D array

For example :for (int x=0;x

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Read Data from Array

for(int x=0;x

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Examine the following:double values[][] = {

{1.2, 9.0, 3.2},

{9.2, 0.5, 1.5, -1.2},

{7.3, 7.9, 4.8}

} ;

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What is the value of values[2][1]?

a. 7.3

b. 7.9

c. 9.2d. There is no such array element

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You need to create an array as given :

12 -9 8

7 14

-32 -1 0

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Choose the correct declaration from the declarationstatements given:

Declaration A Declaration B Declaration C Declaration D

double table [ ][ ]

= { 12, -9, 8,7, 14,

-32, -1, 0} ;

double table[ ][ ]

= { {12, -9, 8},{7, 14, 0},

-32, -1, 0} };

double table[ ][

] = { {12, -9, 8}{7, 14}

{-32, -1, 0} };

double table[ ][

] = { {12, -9, 8},{7, 14},

{-32, -1, 0} };

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Which of the following statements constructs an array

with 5 rows of 7 columns?

long stuff[][] = new stuff[5][7];

long stuff[][] = new long[5][7];

long stuff[][] = long[5][7];

long stuff[][] = long[7][5];

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Which of the following statements that constructs a

two-dimensional array with 7 rows?

int array[ ][ ] = new int[7][ ];

int array[ ][ ] = new int[][];

int array[ ][ ] = new int[ ][7];

int[] array[7] = new int[ ];

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OOP in Java