//determinent
public float Determinant()
{
float determinent = 0;
if(this.Rows != this.Columns)
throw new RtwMatrixException("Attempt to find the determinent of a non square matrix");
//return 0;
//get the determinent of a 2x2 matrix
if(this.Rows == 2 && this.Columns == 2)
{
determinent = (this[0,0] * this[1,1]) - (this[0,1] * this[1,0]);
return determinent;
}
RtwMatrix tempMtx = new RtwMatrix(this.Rows - 1, this.Columns - 1);
//find the determinent with respect to the first row
for(int j = 0; j < this.Columns; j++)
{
tempMtx = this.Minor(0, j);
//recursively add the determinents
determinent += (int)Math.Pow(-1, j) * this[0,j] * tempMtx.Determinant();
}
return determinent;
}
//adjoint matrix
public RtwMatrix Adjoint()
{
if(this.Rows < 2 || this.Columns < 2)
throw new RtwMatrixException("Adjoint matrix not available");
RtwMatrix tempMtx = new RtwMatrix(this.Rows-1 , this.Columns-1);
RtwMatrix adjMtx = new RtwMatrix (this.Columns , this.Rows);
for(int i = 0; i < this.Rows; i++)
{
for(int j = 0; j < this.Columns;j++)
{
tempMtx = this.Minor(i, j);
//put the determinent of the minor in the transposed position
adjMtx[j,i] = (int)Math.Pow(-1,i+j) * tempMtx.Determinant();
}
}
return adjMtx;
}