/// <summary>
/// Returns a new matrix as submatrix of current matrix.
/// </summary>
/// <param name="rows">Number of rows in submatrix.</param>
/// <param name="columns">Number of columns in submatrix.</param>
/// <returns></returns>
public MyMatrix GetSubMatrix(int rows, int columns)
{
if (rows > Rows || columns > Columns || rows < 0 || columns < 0)
{
throw new ArgumentException();
}
MyMatrix result = new MyMatrix(rows, columns);
for (int i = 0; i < result.Rows; i++)
{
for (int j = 0; j < result.Columns; j++)
{
result[i, j] = _matrix[i, j];
}
}
return(result);
}
/// <summary>
/// Multiplies the matrix by the number.
/// </summary>
/// <param name="m1">Matrix to multiply.</param>
/// <param name="number">Number to multiply.</param>
/// <returns>New matrix.</returns>
public static MyMatrix operator *(MyMatrix m1, int number)
{
if (m1 is null)
{
throw new ArgumentNullException();
}
if (m1.Length == 0)
{
throw new ArgumentException();
}
MyMatrix result = new MyMatrix(m1.Rows, m1.Columns);
for (int i = 0; i < result.Rows; i++)
{
for (int j = 0; j < result.Columns; j++)
{
result[i, j] = m1[i, j] * number;
}
}
return(result);
}
/// <summary>
/// Subtracts two matrixes.
/// </summary>
/// <param name="m1">First matrix to subtract.</param>
/// <param name="m2">Second matrix to subtract.</param>
/// <returns>New matrix.</returns>
public static MyMatrix operator -(MyMatrix m1, MyMatrix m2)
{
if (m1 is null || m2 is null)
{
throw new ArgumentNullException();
}
if (m1.Rows != m2.Rows || m1.Columns != m2.Columns || m2.Length == 0 || m1.Length == 0)
{
throw new ArgumentException();
}
MyMatrix result = new MyMatrix(m1.Rows, m1.Columns);
for (int i = 0; i < result.Rows; i++)
{
for (int j = 0; j < result.Columns; j++)
{
result[i, j] = m1[i, j] - m2[i, j];
}
}
return(result);
}