What is matrix class? Describe it with example and uses.
- A matrix is simply a 2-D array, which is widely used in scientific programming to perform calculations. There are various ways to implement matrix class: using arrays, using pointers, using vectors.
- Let us look at an example of matrix class using pointers :
class matrix
{
int **p, m, n;
public:
matrix(int row = 2, col = 2)
{
m = row;
n = col;
p = new(int *) [m];
for (int i = 0; i < m; i++)
p[i] = new int[n];
}
~matrix()
{
for (int i = 0; i < m; i++)
delete p[i];
delete p;
}
void accept()
{
cout<<”Enter matrix elements:”;
for(int i = 0; i < m; i++)
{
for(int j = 0; j < n; j++)
{
cin >> p[i][j];
}
}
}
void display()
{
cout <<”The matrix is:”;
for(int i = 0; i < m; i++)
{
cout <<endl;
for(int j = 0; j < n; j++)
{
cout << p[i][j] <<” “;
}
}
}
matrix operator +(matrix m2)
{
matrix T(m, n);
for(int i = 0; i < m; i++)
{
for(int j = 0; j < n; j++)
{
T.p[i][j] = p[i][j] + m2.p[i][j];
}
}
return T;
}
friend matrix operator * (matrix, matrix);
};
matrix operator * (matrix a , matrix b)
{
if(a.n == b.m)
{
matrix T(a.m, b.n);
for(int i = 0; i < a.m; i++)
{
for(int k = 0; k < b.n; k++)
{
T.p[i][k] = 0;
for(int j = 0; j < a.n; j++)
{
T.p[i][k]+= a.p[i][j] * b.p[j][k];
}
}
}
return T;
}
}
- Here, the class supports addition and multiplication functions. We can expand it to have subtraction function.
