C++ Matrix Help

#include<iostream>

using namespace std;

class Matrix
{
private:
    int rows, columns;
    double** data;
public:
    Matrix()
    {
        rows = 0;
        columns = 0;
        data = NULL;
    }
    Matrix(int r, int c)
    {
        rows = r;
        columns = c;
        double** matrixArray = new double*[rows];
        for (int i = 0; i < rows; i++) {
            matrixArray[i] = new double[columns];
            for (int j = 0; j < columns; j++) {
                matrixArray[i][j] = 0.0;
            }
        }
        data = matrixArray;
    }
    ~Matrix()
    {
        if(data != NULL)
        {
        for(int i = 0; i < rows; i++)
        {
            delete[] data[i];
        }
        delete[] data;
        }
    }
    int getRows();
    int getColumns();
    void Resize(int, int);
    double getValue(int, int);
    void setValue(int, int, double);
};

int Matrix::getRows()
{
    return rows;
}

int Matrix::getColumns()
{
    return columns;
}

void Matrix::Resize(int r, int c)
{
    rows = r;
    columns = c;
    if(data != NULL)
    {
        for(int i = 0; i < rows; i++)
        {
            delete[] data[i];
        }
        delete[] data;
    }
    Matrix(r,c);
}

double Matrix::getValue(int r, int c)
{
    return data[r][c];
}

void Matrix::setValue(int r, int c, double d)
{
    data[r][c] = d;
}

int main()
{
    int r;
    cout << "Give rows\n";
    cin >> r;
    Matrix m1;
    Matrix m2(r,1);
    m1.Resize(r,1);
    for(int i = 0; i < r; i++)
    {
        double t;
        cout << "Give data for row " << i+1 << " on matrix 1";
        cin >> t;
        m1.setValue(i, 1, t);
    }
    for(int i = 0; i < r; i++)
    {
        double t = m1.getValue(i, 1);
       cout << t;
    }
    return 0;
}