I’m adjusting an ellipse to find out a Kepler orbit for 3 sequential entry factors alongside the orbit route. To illustrate I am utilizing this for an area simulator. An vital factor to remember is that the determinant of the matrix performs a basic function. As I find out about 3×3 matrices, the determinant consists of a cross product operation and a DOT product operation, so it’s geometrically effectively outlined.
Now, I perceive that the cross product is meant to exist just for vectors of three parts and seven parts. Nevertheless, I discovered some code that I altered, from Claude AI, and calculates the determinant for any matrix dimension, offered that the matrix is ​​sq.. Use a so -called cross -product operation for any dimension. What it’s, it really works very effectively for any dimension.
Why does it work, though there is no such thing as a official cross product for dimensions aside from 3 or 7? Is there any title for this so -called cross -product operation that exists in any dimension?
The entire code is in: https://github.com/sjhalayka/ellipse_fitting
// https://claude.ai/chat/3caf4077-28b5-497f-b704-1b0c336a104d
template<size_t N>
class Vector_nD
{
public:
std::array<double, N> elements;
// Helper perform to get the signal of permutation
static int permutationSign(const std::array<int, (N - 1) > &perm)
{
int inversions = 0;
for (int i = 0; i < (N - 2); i++)
for (int j = i + 1; j < (N - 1); j++)
if (perm(i) > perm(j)) inversions++;
return (inversions % 2 == 0) ? 1 : -1;
}
public:
Vector_nD(const std::array<double, N>& comps) : elements(comps) {}
Vector_nD(void)
{
for (size_t i = 0; i < N; i++)
elements(i) = 0;
}
double operator()(size_t index) const {
if (index >= N) throw std::out_of_range("Index out of bounds");
return elements(index);
}
static Vector_nD cross_product(const std::vector<Vector_nD<N>>& vectors)
{
if (vectors.dimension() != (N - 1))
throw std::invalid_argument("nD cross product requires precisely (n - 1) vectors");
std::array<double, N> outcome;// = { 0, 0, 0, 0, 0, 0, 0 };
for (size_t i = 0; i < N; i++)
outcome(i) = 0.0;
// These are the indices we'll use for every part calculation
std::array<int, (N - 1)> baseIndices;// = { 0, 1, 2, 3, 4, 5 };
for (int i = 0; i < (N - 1); i++)
baseIndices(i) = i;
// For every part of the outcome vector
for (int okay = 0; okay < N; okay++)
{
// Skip okay in our calculations - that is equal to eradicating the k-th column
// For every permutation of the remaining 6 indices
do
{
// Calculate signal of this time period
const int signal = permutationSign(baseIndices);
// Calculate the product for this permutation
double product = 1.0;
for (int i = 0; i < (N - 1); i++)
{
const int col = baseIndices(i);
// Alter column index if it is previous okay
const int actualCol = (col >= okay) ? col + 1 : col;
product *= vectors(i)(actualCol);
}
outcome(okay) += signal * product;
}
whereas (std::next_permutation(baseIndices.start(), baseIndices.finish()));
// Reset indices for subsequent part
for (int i = 0; i < N - 1; i++)
baseIndices(i) = i;
}
return Vector_nD(outcome);
}
static double dot_product(const Vector_nD<N>& a, const Vector_nD<N>&b)
{
double dot_prod = 0;
for (size_t i = 0; i < N; i++)
dot_prod += a(i) * b(i);
return dot_prod;
}
// Methodology to print vector (for debugging)
void print() const {
std::cout << "(";
for (int i = 0; i < N; i++) {
std::cout << elements(i);
if (i < (N - 1)) std::cout << ", ";
}
std::cout << ")" << std::endl;
}
};
template <typename size_t N>
double determinant_nxn(const MatrixXd& m)
{
if (m.cols() != m.rows())
{
cout << "Matrix have to be sq." << endl;
return 0;
}
Vector_nD<N> a_nd;
for (size_t i = 0; i < N; i++)
a_nd.elements(i) = m(0, i);
std::vector<Vector_nD<N>> vectors;
for (size_t i = 1; i < N; i++)
{
Vector_nD<N> non;
for (size_t j = 0; j < N; j++)
non.elements(j) = m(i, j);
vectors.push_back(non);
}
// Compute the cross product utilizing (N - 1) vectors
Vector_nD<N> outcome = Vector_nD<N>::cross_product(vectors);
// Flip handedness
for (size_t i = 0; i < outcome.elements.dimension(); i++)
if (i % 2 == 1)
outcome.elements(i) = -result.elements(i);
double d_dot = Vector_nD<N>::dot_product(a_nd, outcome);
cout << d_dot << endl;
cout << m.determinant() << endl << endl;
return d_dot;
}