Rational operator- (const Rational& a, const Rational& b)
{
int gcd = GCD(a.denom, b.denom);
int newNumer = a.numer*(b.denom / gcd) - b.numer*(a.denom / gcd);
int newDenom = a.denom*(b.denom / gcd);
signCheck(newNumer, newDenom);
return Rational(newNumer, newDenom, true);//Boolean is extra flag to prevent reduction by GCD again
}
Rational operator/ (const Rational& a, const Rational& b)
{
int c = GCD(a.numer, b.numer);
int d = GCD(b.denom, a.denom);
int newNumer = (a.numer / c)*(b.denom / d);
int newDenom = (a.denom / d)*(b.numer / c);
signCheck(newNumer, newDenom);
return Rational(newNumer, newDenom, true);//Boolean is extra flag to prevent reduction by GCD again
}
// Public Methods
void // computes the normal to a set of points thanks to PCA method
PCA::compute()
{
computeCentre();
Eigen::Matrix3d covar;
computeCovar( covar );
// Compute Eigenvectors & Eigenvalues
Eigen::SelfAdjointEigenSolver<Eigen::Matrix3d> eigensolver(covar);
// Order the vectors by eigenvalues
int order [3] = {0,1,2};
int temp = 0;
for(size_t i = 0; i < 3; i++)
{
for (size_t j = i; j < 3; j++)
{
if( (eigensolver.eigenvalues())(i) > (eigensolver.eigenvalues())(j) )
{
temp = order [j];
order [j] = order [i];
order [i] = temp;
}
}
}
normal = ( eigensolver.eigenvectors() ).col( order[0] );
vec_base1 = ( eigensolver.eigenvectors() ).col( order[1] ) ;
signCheck();
vec_base2 = normal.cross( vec_base1 );
if (normal.norm()!=normal.norm()){
std::cerr << "Error PCA::compute NaN Normal: " << std::endl;
std::cerr << normal << std::endl;
}
if (normal.norm() == 0)
std::cerr << "Error PCA::compute Null Normal" << std::endl;
}
