C Program to Perform Scalar Multiplication of a Matrix

Introduction

Scalar multiplication of a matrix involves multiplying each element of the matrix by a scalar value. This guide will show you how to write a C program that performs scalar multiplication of a matrix provided by the user.

Problem Statement

Create a C program that:

• Takes a matrix and a scalar value as input from the user.
• Multiplies each element of the matrix by the scalar value.
• Displays the resulting matrix.

Example:

• Input:
  • Matrix:

    1 2 3
    4 5 6
    7 8 9
    

  • Scalar: 2
• Output: Resulting Matrix:

  2 4 6
  8 10 12
  14 16 18
  

Solution Steps

1. Include the Standard Input-Output Library: Use #include <stdio.h> for standard input-output functions.
2. Write the Main Function: Define the main function, which is the entry point of every C program.
3. Declare Variables: Declare variables to store the matrix, its dimensions, the scalar value, and loop counters.
4. Input the Dimensions and Elements of the Matrix: Use loops to take input from the user for the matrix.
5. Input the Scalar Value: Use scanf to take input for the scalar value.
6. Perform Scalar Multiplication: Use nested loops to multiply each element of the matrix by the scalar value.
7. Display the Resulting Matrix: Use loops to display the resulting matrix.

C Program to Perform Scalar Multiplication of a Matrix

#include <stdio.h>

int main() {
    // Step 1: Declare variables to hold the matrix, dimensions, and scalar
    int rows, cols;
    int matrix[100][100];
    int scalar;
    int i, j;

    // Step 2: Prompt the user to enter the dimensions of the matrix
    printf("Enter the number of rows and columns of the matrix: ");
    scanf("%d %d", &rows, &cols);

    // Step 3: Input the elements of the matrix
    printf("Enter elements of the matrix:\n");
    for (i = 0; i < rows; i++) {
        for (j = 0; j < cols; j++) {
            scanf("%d", &matrix[i][j]);
        }
    }

    // Step 4: Input the scalar value
    printf("Enter the scalar value: ");
    scanf("%d", &scalar);

    // Step 5: Perform scalar multiplication
    for (i = 0; i < rows; i++) {
        for (j = 0; j < cols; j++) {
            matrix[i][j] *= scalar;
        }
    }

    // Step 6: Display the resulting matrix
    printf("Resulting matrix after scalar multiplication:\n");
    for (i = 0; i < rows; i++) {
        for (j = 0; j < cols; j++) {
            printf("%d ", matrix[i][j]);
        }
        printf("\n");
    }

    return 0;  // Step 7: Return 0 to indicate successful execution
}

Explanation

Step 1: Declare Variables

• The variables rows and cols store the dimensions of the matrix. The matrix array stores the elements of the matrix. The variable scalar stores the scalar value by which the matrix will be multiplied. The variables i and j are used as loop counters.

Step 2: Input the Dimensions of the Matrix

• The program prompts the user to enter the number of rows and columns for the matrix using scanf.

Step 3: Input the Elements of the Matrix

• The program uses nested for loops to take input for each element of the matrix from the user.

Step 4: Input the Scalar Value

• The program prompts the user to enter the scalar value using scanf.

Step 5: Perform Scalar Multiplication

• The program uses nested for loops to iterate through each element of the matrix:
  • Each element is multiplied by the scalar value, and the result is stored back in the matrix.

Step 6: Display the Resulting Matrix

• The program uses nested for loops to display the elements of the resulting matrix after scalar multiplication.

Step 7: Return 0

• The return 0; statement indicates that the program executed successfully.

Output Example

Example 1:

Enter the number of rows and columns of the matrix: 3 3
Enter elements of the matrix:
1 2 3
4 5 6
7 8 9
Enter the scalar value: 2
Resulting matrix after scalar multiplication:
2 4 6 
8 10 12 
14 16 18

Example 2:

Enter the number of rows and columns of the matrix: 2 2
Enter elements of the matrix:
10 20
30 40
Enter the scalar value: 3
Resulting matrix after scalar multiplication:
30 60 
90 120

Conclusion

This C program demonstrates how to perform scalar multiplication of a matrix by multiplying each element by a scalar value. It covers basic concepts such as arrays, loops, and matrix operations, making it a useful example for beginners learning C programming.