Matrix Multiplication in C

How to perform matrix multiplication in C? Matrix multiplication is a common operation in scientific computing, computer graphics, and various mathematical applications. In this article, we will provide a step-by-step guide on how to perform matrix multiplication in the C programming language.

Matrix Multiplication

Matrix multiplication is a binary operation in which two matrices as the input and another matrix is the output. If matrix A has dimension mxn and matrix B has dimenssion nxp then resultant matrix C will have dimenssion mxp. Each element in the product matrix C is obtained by multiplying elements from corresponding rows of matrix A and columns of B, followed by summing the products.

C Program for Matrix Multiplication

#include <stdio.h>
void main()
{
    int m1, m2, n1, n2;
    printf("Enter the number of rows in first matrix ");
    scanf("%d", &n1);
    printf("Enter the number of column in first matrix ");
    scanf("%d", &m1);
    printf("Enter the number of rows in second matrix ");
    scanf("%d", &n2);
    printf("Enter the number of column in second matrix ");
    scanf("%d", &m2);
    if (m1 != n2)
    {
        printf("Matrix multiplication is not possible ");
    }
    else
    {
        int A[n1][m1], B[n2][m2], C[n1][m2];
        printf("Enter the element of first Matrix\n");
        for (int i = 0; i < n1; i++)
        {
            for (int j = 0; j < m1; j++)
            {
                printf("Enter the element at position {%d,%d}", i, j);
                scanf("%d", &A[i][j]);
            }
        }
        printf("Enter the element of second Matrix\n");
        for (int i = 0; i < n2; i++)
        {
            for (int j = 0; j < m2; j++)
            {
                printf("Enter the element at position {%d,%d}", i, j);
                scanf("%d", &B[i][j]);
            }
        }
        // loop[ for matrix multiplication
        for (int i = 0; i < n1; i++)
        {
            for (int j = 0; j < m1; j++)
            {
                C[i][j] = 0;
                for (int k = 0; k < m1; k++)
                {
                    C[i][j] += A[i][k] * B[k][j];
                
            }
        }
        printf("Result after matrix multiplication\n ");
        for (int i = 0; i < n1; i++)
        {
            for (int j = 0; j < m2; j++)
            {
                printf("%d\t", C[i][j]);
            }
            printf("\n");
        }
    }
}

Output

Explanation of the above C Program

• The above C program starts by asking users to enter the dimensions of both matrices.
• After that program checks if matrixmultiplication is possible or not if (m1 != n2).
• After that program declares three matrices A, B, and C with dimensions specified by the user.
• The program asks the user to enter the elements of both matrices.
• Perform the matrix multiplication by using three for loop and store the result in matrix C.
• At the end, the program prints the result after matrix multiplication.

See Also

• Matrix Addition in C
• Transpose of Matrix in C