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The posted class provides input/print routines but no arithmetic implementations. Common issues to address before adding methods: allocate the storage after reading rows/columns (avoid a fixed 10x10), use double if inversion/division is required, and always check dimensions (and singularity for inversion). was correct to ask for more detail; the code below is a concise, drop-in utility showing safe add/subtract/multiply and a simple Gauss–Jordan inverse (partial pivoting). Division is implemented as A * inverse(B).

public final class MatrixOps {
    private MatrixOps() {}

    public static double[][] add(double[][] A, double[][] B) {
        int r = A.length, c = A[0].length;
        if (B.length != r || B[0].length != c) throw new IllegalArgumentException("Dimension mismatch");
        double[][] R = new double[r][c];
        for (int i = 0; i < r; i++)
            for (int j = 0; j < c; j++)
                R[i][j] = A[i][j] + B[i][j];
        return R;
    }

    public static double[][] sub(double[][] A, double[][] B) {
        int r = A.length, c = A[0].length;
        if (B.length != r || B[0].length != c) throw new IllegalArgumentException("Dimension mismatch");
        double[][] R = new double[r][c];
        for (int i = 0; i < r; i++)
            for (int j = 0; j < c; j++)
                R[i][j] = A[i][j] - B[i][j];
        return R;
    }

    public static double[][] mul(double[][] A, double[][] B) {
        int r = A.length, inner = A[0].length;
        if (B.length != inner) throw new IllegalArgumentException("Inner dimensions must match");
        int c = B[0].length;
        double[][] R = new double[r][c];
        for (int i = 0; i < r; i++) {
            for (int k = 0; k < inner; k++) {
                double aik = A[i][k];
                for (int j = 0; j < c; j++) R[i][j] += aik * B[k][j];
            }
        }
        return R;
    }

    public static double[][] invert(double[][] a) {
        int n = a.length;
        if (a[0].length != n) throw new IllegalArgumentException("Matrix must be square");
        double[][] aug = new double[n][2*n];
        for (int i = 0; i < n; i++) {
            System.arraycopy(a[i], 0, aug[i], 0, n);
            aug[i][n + i] = 1.0;
        }
        for (int i = 0; i < n; i++) {
            int pivot = i;
            for (int r = i + 1; r < n; r++)
                if (Math.abs(aug[r][i]) > Math.abs(aug[pivot][i])) pivot = r;
            if (Math.abs(aug[pivot][i]) < 1e-12) throw new IllegalArgumentException("Singular or nearly singular");
            if (pivot != i) { double[] tmp = aug[i]; aug[i] = aug[pivot]; aug[pivot] = tmp; }
            double div = aug[i][i];
            for (int j = 0; j < 2*n; j++) aug[i][j] /= div;
            for (int r = 0; r < n; r++) if (r != i) {
                double f = aug[r][i];
                for (int j = 0; j < 2*n; j++) aug[r][j] -= f * aug[i][j];
            }
        }
        double[][] inv = new double[n][n];
        for (int i = 0; i < n; i++) System.arraycopy(aug[i], n, inv[i], 0, n);
        return inv;
    }

    public static double[][] div(double[][] A, double[][] B) {
        return mul(A, invert(B));
    }
}

Notes and cautions: the Gauss–Jordan inverter shown is fine for small matrices and learning, but is not tuned for stability or performance—use a tested library (Apache Commons Math, EJML, etc.) for production. For integer-only problems, avoid inverses (integers often do not form a field); prefer solving linear systems or using rational arithmetic. To integrate with the posted class, allocate the storage after reading dimensions, fill a double[][], and call these utilities.

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Member Avatar for masijade

Thanks for what?

We are definately not going to do it for you, especially when you can't even take the time to describe your problem.

Show your code, provide a good, but short, description of the current problems with it, and provide any and all error/compiler messages and we may help you solve it (although I don't know about that after this pitiful plea).

Member Avatar for OcarinaSensei 
import java.util.Scanner;
public class Matrix
{
   public Matrix() 
   {
     
   }
   public void enterMatrix()
   {
      Scanner input = new Scanner(System.in);
      System.out.print("Enter number of rows -> ");
      r=input.nextInt();
      System.out.print("Enter numerof columns -> ");
      c=input.nextInt();
      for(int i=0;i<r;i++)
      {
         for (int j=0;j<c;j++)
         {
             System.out.print("Enter value at row "+i+", column "+j+" -> ");
             m[i][j]=input.nextInt();
         }
      }
   }
   public void printMatrix()
   {
       for (int i=0;i<r;i++)
       {
           for (int j=0;j<c;j++)
           {
               System.out.print(m[i][j]+" ");
           }
           System.out.println();
       }
    }
   public void multMatrix()
   {
       
    }
   int[][] m = new int[10][10];
   int r;
   int c;
   }

and the test

public class MatrixTest
{
  public static void main (String[] args)
  {
      Matrix a=new Matrix();
      a.enterMatrix();
      a.printMatrix();
  }
}
Member Avatar for masijade

Okay? And the rest of the methods?

Member Avatar for OcarinaSensei

Yeah... that's all I got.
I was hoping you guys could help with the rest of the methods

Member Avatar for masijade

Well, I believe I said in the first reply that we weren't going to do it for you.

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