# Find Scalar Multiplication of a Matrix in Java?

In Java, Array is an object. It is a non-primitive data type which stores values of similar data type. The matrix in java is nothing but a multi-dimensional array which represents multiple rows and columns.

Scalar multiplication is nothing but multiplication between a matrix and a real number. The result of this multiplication is in matrix format.

As per the problem statement, we have to find the scalar multiplication of a matrix.

Let’s deep dive into this article, to know how it can be done by using Java programming language.

## To show you some instances

### Instance-1

Suppose the original matrix is {
{10, 20, 30},
{40, 50, 60},
{70, 80, 90}
}


Scalar value: 5

Resultant Matrix −
50 100 150
200 250 300
350 400 450


### Instance-2

Suppose the original matrix is {
{10, 20, 30, 40},
{40, 50, 60, 20},
{70, 80, 90, 90}
}


Scalar value: 12

Resultant Matrix −
120 240  360
480 600  720
840 960 1080


### Instance-3

Suppose the original matrix is {
{12, 123, 12131},
{11, 67, 896},
{233, 234, 678}
}


Scalar value: 3

Resultant Matrix −
36 	369 	36393
33 	201 	2688
699 	702 	2034


### Algorithm

Step 1 − Declare and initialize an integer type multi-dimensional array.

Step 2 − Declare another empty integer type multi-dimensional array to store the resultant matrix elements.

Step 3 − Initiate a nested for loop to multiply the scalar value with the given matrix elements and store those product values into that empty matrix.

Step 4 − Print the resultant matrix as output.

### Syntax

To get the length of an array (number of elements in that array), there is an inbuilt property of array i.e length

Below refers to the syntax of it-

array.length;

where, ‘array’ refers to the array reference.

### Multiple Approaches

We have provided the solution in different approaches.

• By Using Static Initialization of Matrix

• By Using User Defined Method

Let’s see the program along with its output one by one.

## Approach-1: By Using Static Initialization of Matrix

In this approach, array elements will be initialized in the program. Then as per the algorithm calculate the scalar multiplication.

### Example

public class Main {
public static void main(String[] args) {

//declare and initialize an integer type multi- dimensional array
int inputMatrix[][] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};

//declare a variable to store scalar value
int s = 2;

//declare a variable to store the given matrix length value
int len = inputMatrix.length;
System.out.println("Given Matrix: ");
for (int i = 0; i < len; i++){
for (int j = 0; j < len; j++){
System.out.print(inputMatrix[i][j] + " ");
}
System.out.println();
}
System.out.println("The scalar value is: " + s);

//declare an empty integer type multi- dimensional array
int temp[][] = new int[len][len];

//initiate the loop to calculate the scalar Multiplication
for (int i = 0; i < len; i++) {
for (int j = 0; j < len; j++){
temp[i][j] = inputMatrix[i][j] * s;
}
}
System.out.println("The scalar multiplication of given Matrix is: ");

//initiate the loop to print the resultant matrix
for (int i = 0; i < len; i++){
for (int j = 0; j < len; j++){
System.out.print(temp[i][j] + " ");
}
System.out.println();
}
}
}


### Output

Given Matrix:
1 2 3
4 5 6
7 8 9
The scalar value is: 2
The scalar multiplication of given Matrix is:
2 4 6
8 10 12
14 16 18


## Approach-2: By Using Dynamic Initialization of Matrix

In this approach, array elements will be initialized in the program. Then call a user defined method by passing this array as parameter. Inside the method as per the algorithm calculate the scalar multiplication of the matrix.

### Example

public class Main {
public static void main(String[] args) {
//declare an integer type multi- dimensional array and add some random values
int matrix[][] = {{11, 22, 34}, {42, 25, 61}, {72, 83, 94}};
//declare a variable to store scalar value
int scalar = 10;
//call the user-defined method
scalarMultiplication(matrix,scalar);
}
//user-defined method to calculate the scalar Multiplication
public static void scalarMultiplication(int[][] inputMatrix, int s) {
//declare a variable to store the given matrix length value
int len = inputMatrix.length;
System.out.println("Given Matrix: ");
for (int i = 0; i < len; i++){
for (int j = 0; j < len; j++){
System.out.print(inputMatrix[i][j] + " ");
}
System.out.println();
}
System.out.println("The scalar value is: " + s);
//declare an empty integer type multi- dimensional array
int temp[][] = new int[len][len];
//initiate the loop to calculate the scalar Multiplication
for (int i = 0; i < len; i++) {
for (int j = 0; j < len; j++){
temp[i][j] = inputMatrix[i][j] * s;
}
}
//output screen
System.out.println("The scalar multiplication of given Matrix is: ");
//initiate the loop to print the resultant matrix
for (int i = 0; i < len; i++){
for (int j = 0; j <len; j++){
System.out.print(temp[i][j] + " ");
}
System.out.println();
}
}
}


### Output

Given Matrix:
11 22 34
42 25 61
72 83 94
The scalar value is: 10
The scalar multiplication of given Matrix is:
110 220 340
420 250 610
720 830 940


In this article, we explored different approaches to find scalar multiplication of a matrix by using Java programming language.