public static decimal Determinant(NMatrix matrix)
{
if (matrix.Rows != matrix.Columns)
{
throw new ArgumentException("Determinant calculation failed - the matrix wasn't square.");
}
decimal result = 0;
if (matrix.Rows == 0)
{
}
else if (matrix.Rows == 1)
{
result = matrix.Data[0, 0];
}
else
{
NMatrix cfs;
try
{
cfs = NMatrix.Cofactors(matrix);
}
catch (ArgumentException)
{
// IS THIS CORRECT?!
throw new ArgumentException("Determinant calculation failed - this was likely because its determinant was undifined.");
}
for (int i = 0; i < matrix.Columns; i++)
{
result += matrix.Data[0, i] * cfs.Data[0, i];
}
}
return(result);
}
public static NMatrix Adjoint(NMatrix matrix)
{
return(matrix.Cofactors().T());
}
public IMatrix CofactorsMatrix()
{
return(NMatrix.Cofactors(this));
}