summaryrefslogtreecommitdiff
path: root/glm-master/glm/gtx/pca.inl
diff options
context:
space:
mode:
Diffstat (limited to 'glm-master/glm/gtx/pca.inl')
-rw-r--r--glm-master/glm/gtx/pca.inl343
1 files changed, 0 insertions, 343 deletions
diff --git a/glm-master/glm/gtx/pca.inl b/glm-master/glm/gtx/pca.inl
deleted file mode 100644
index d5a24b7..0000000
--- a/glm-master/glm/gtx/pca.inl
+++ /dev/null
@@ -1,343 +0,0 @@
-/// @ref gtx_pca
-
-#ifndef GLM_HAS_CXX11_STL
-#include <algorithm>
-#else
-#include <utility>
-#endif
-
-namespace glm {
-
-
- template<length_t D, typename T, qualifier Q>
- GLM_INLINE mat<D, D, T, Q> computeCovarianceMatrix(vec<D, T, Q> const* v, size_t n)
- {
- return computeCovarianceMatrix<D, T, Q, vec<D, T, Q> const*>(v, v + n);
- }
-
-
- template<length_t D, typename T, qualifier Q>
- GLM_INLINE mat<D, D, T, Q> computeCovarianceMatrix(vec<D, T, Q> const* v, size_t n, vec<D, T, Q> const& c)
- {
- return computeCovarianceMatrix<D, T, Q, vec<D, T, Q> const*>(v, v + n, c);
- }
-
-
- template<length_t D, typename T, qualifier Q, typename I>
- GLM_FUNC_DECL mat<D, D, T, Q> computeCovarianceMatrix(I const& b, I const& e)
- {
- glm::mat<D, D, T, Q> m(0);
-
- size_t cnt = 0;
- for(I i = b; i != e; i++)
- {
- vec<D, T, Q> const& v = *i;
- for(length_t x = 0; x < D; ++x)
- for(length_t y = 0; y < D; ++y)
- m[x][y] += static_cast<T>(v[x] * v[y]);
- cnt++;
- }
- if(cnt > 0)
- m /= static_cast<T>(cnt);
-
- return m;
- }
-
-
- template<length_t D, typename T, qualifier Q, typename I>
- GLM_FUNC_DECL mat<D, D, T, Q> computeCovarianceMatrix(I const& b, I const& e, vec<D, T, Q> const& c)
- {
- glm::mat<D, D, T, Q> m(0);
- glm::vec<D, T, Q> v;
-
- size_t cnt = 0;
- for(I i = b; i != e; i++)
- {
- v = *i - c;
- for(length_t x = 0; x < D; ++x)
- for(length_t y = 0; y < D; ++y)
- m[x][y] += static_cast<T>(v[x] * v[y]);
- cnt++;
- }
- if(cnt > 0)
- m /= static_cast<T>(cnt);
-
- return m;
- }
-
- namespace _internal_
- {
-
- template<typename T>
- GLM_INLINE T transferSign(T const& v, T const& s)
- {
- return ((s) >= 0 ? glm::abs(v) : -glm::abs(v));
- }
-
- template<typename T>
- GLM_INLINE T pythag(T const& a, T const& b) {
- static const T epsilon = static_cast<T>(0.0000001);
- T absa = glm::abs(a);
- T absb = glm::abs(b);
- if(absa > absb) {
- absb /= absa;
- absb *= absb;
- return absa * glm::sqrt(static_cast<T>(1) + absb);
- }
- if(glm::equal<T>(absb, 0, epsilon)) return static_cast<T>(0);
- absa /= absb;
- absa *= absa;
- return absb * glm::sqrt(static_cast<T>(1) + absa);
- }
-
- }
-
- template<length_t D, typename T, qualifier Q>
- GLM_FUNC_DECL unsigned int findEigenvaluesSymReal
- (
- mat<D, D, T, Q> const& covarMat,
- vec<D, T, Q>& outEigenvalues,
- mat<D, D, T, Q>& outEigenvectors
- )
- {
- using _internal_::transferSign;
- using _internal_::pythag;
-
- T a[D * D]; // matrix -- input and workspace for algorithm (will be changed inplace)
- T d[D]; // diagonal elements
- T e[D]; // off-diagonal elements
-
- for(length_t r = 0; r < D; r++)
- for(length_t c = 0; c < D; c++)
- a[(r) * D + (c)] = covarMat[c][r];
-
- // 1. Householder reduction.
- length_t l, k, j, i;
- T scale, hh, h, g, f;
- static const T epsilon = static_cast<T>(0.0000001);
-
- for(i = D; i >= 2; i--)
- {
- l = i - 1;
- h = scale = 0;
- if(l > 1)
- {
- for(k = 1; k <= l; k++)
- {
- scale += glm::abs(a[(i - 1) * D + (k - 1)]);
- }
- if(glm::equal<T>(scale, 0, epsilon))
- {
- e[i - 1] = a[(i - 1) * D + (l - 1)];
- }
- else
- {
- for(k = 1; k <= l; k++)
- {
- a[(i - 1) * D + (k - 1)] /= scale;
- h += a[(i - 1) * D + (k - 1)] * a[(i - 1) * D + (k - 1)];
- }
- f = a[(i - 1) * D + (l - 1)];
- g = ((f >= 0) ? -glm::sqrt(h) : glm::sqrt(h));
- e[i - 1] = scale * g;
- h -= f * g;
- a[(i - 1) * D + (l - 1)] = f - g;
- f = 0;
- for(j = 1; j <= l; j++)
- {
- a[(j - 1) * D + (i - 1)] = a[(i - 1) * D + (j - 1)] / h;
- g = 0;
- for(k = 1; k <= j; k++)
- {
- g += a[(j - 1) * D + (k - 1)] * a[(i - 1) * D + (k - 1)];
- }
- for(k = j + 1; k <= l; k++)
- {
- g += a[(k - 1) * D + (j - 1)] * a[(i - 1) * D + (k - 1)];
- }
- e[j - 1] = g / h;
- f += e[j - 1] * a[(i - 1) * D + (j - 1)];
- }
- hh = f / (h + h);
- for(j = 1; j <= l; j++)
- {
- f = a[(i - 1) * D + (j - 1)];
- e[j - 1] = g = e[j - 1] - hh * f;
- for(k = 1; k <= j; k++)
- {
- a[(j - 1) * D + (k - 1)] -= (f * e[k - 1] + g * a[(i - 1) * D + (k - 1)]);
- }
- }
- }
- }
- else
- {
- e[i - 1] = a[(i - 1) * D + (l - 1)];
- }
- d[i - 1] = h;
- }
- d[0] = 0;
- e[0] = 0;
- for(i = 1; i <= D; i++)
- {
- l = i - 1;
- if(!glm::equal<T>(d[i - 1], 0, epsilon))
- {
- for(j = 1; j <= l; j++)
- {
- g = 0;
- for(k = 1; k <= l; k++)
- {
- g += a[(i - 1) * D + (k - 1)] * a[(k - 1) * D + (j - 1)];
- }
- for(k = 1; k <= l; k++)
- {
- a[(k - 1) * D + (j - 1)] -= g * a[(k - 1) * D + (i - 1)];
- }
- }
- }
- d[i - 1] = a[(i - 1) * D + (i - 1)];
- a[(i - 1) * D + (i - 1)] = 1;
- for(j = 1; j <= l; j++)
- {
- a[(j - 1) * D + (i - 1)] = a[(i - 1) * D + (j - 1)] = 0;
- }
- }
-
- // 2. Calculation of eigenvalues and eigenvectors (QL algorithm)
- length_t m, iter;
- T s, r, p, dd, c, b;
- const length_t MAX_ITER = 30;
-
- for(i = 2; i <= D; i++)
- {
- e[i - 2] = e[i - 1];
- }
- e[D - 1] = 0;
-
- for(l = 1; l <= D; l++)
- {
- iter = 0;
- do
- {
- for(m = l; m <= D - 1; m++)
- {
- dd = glm::abs(d[m - 1]) + glm::abs(d[m - 1 + 1]);
- if(glm::equal<T>(glm::abs(e[m - 1]) + dd, dd, epsilon))
- break;
- }
- if(m != l)
- {
- if(iter++ == MAX_ITER)
- {
- return 0; // Too many iterations in FindEigenvalues
- }
- g = (d[l - 1 + 1] - d[l - 1]) / (2 * e[l - 1]);
- r = pythag<T>(g, 1);
- g = d[m - 1] - d[l - 1] + e[l - 1] / (g + transferSign(r, g));
- s = c = 1;
- p = 0;
- for(i = m - 1; i >= l; i--)
- {
- f = s * e[i - 1];
- b = c * e[i - 1];
- e[i - 1 + 1] = r = pythag(f, g);
- if(glm::equal<T>(r, 0, epsilon))
- {
- d[i - 1 + 1] -= p;
- e[m - 1] = 0;
- break;
- }
- s = f / r;
- c = g / r;
- g = d[i - 1 + 1] - p;
- r = (d[i - 1] - g) * s + 2 * c * b;
- d[i - 1 + 1] = g + (p = s * r);
- g = c * r - b;
- for(k = 1; k <= D; k++)
- {
- f = a[(k - 1) * D + (i - 1 + 1)];
- a[(k - 1) * D + (i - 1 + 1)] = s * a[(k - 1) * D + (i - 1)] + c * f;
- a[(k - 1) * D + (i - 1)] = c * a[(k - 1) * D + (i - 1)] - s * f;
- }
- }
- if(glm::equal<T>(r, 0, epsilon) && (i >= l))
- continue;
- d[l - 1] -= p;
- e[l - 1] = g;
- e[m - 1] = 0;
- }
- } while(m != l);
- }
-
- // 3. output
- for(i = 0; i < D; i++)
- outEigenvalues[i] = d[i];
- for(i = 0; i < D; i++)
- for(j = 0; j < D; j++)
- outEigenvectors[i][j] = a[(j) * D + (i)];
-
- return D;
- }
-
- template<typename T, qualifier Q>
- GLM_INLINE void sortEigenvalues(vec<2, T, Q>& eigenvalues, mat<2, 2, T, Q>& eigenvectors)
- {
- if (eigenvalues[0] < eigenvalues[1])
- {
- std::swap(eigenvalues[0], eigenvalues[1]);
- std::swap(eigenvectors[0], eigenvectors[1]);
- }
- }
-
- template<typename T, qualifier Q>
- GLM_INLINE void sortEigenvalues(vec<3, T, Q>& eigenvalues, mat<3, 3, T, Q>& eigenvectors)
- {
- if (eigenvalues[0] < eigenvalues[1])
- {
- std::swap(eigenvalues[0], eigenvalues[1]);
- std::swap(eigenvectors[0], eigenvectors[1]);
- }
- if (eigenvalues[0] < eigenvalues[2])
- {
- std::swap(eigenvalues[0], eigenvalues[2]);
- std::swap(eigenvectors[0], eigenvectors[2]);
- }
- if (eigenvalues[1] < eigenvalues[2])
- {
- std::swap(eigenvalues[1], eigenvalues[2]);
- std::swap(eigenvectors[1], eigenvectors[2]);
- }
- }
-
- template<typename T, qualifier Q>
- GLM_INLINE void sortEigenvalues(vec<4, T, Q>& eigenvalues, mat<4, 4, T, Q>& eigenvectors)
- {
- if (eigenvalues[0] < eigenvalues[2])
- {
- std::swap(eigenvalues[0], eigenvalues[2]);
- std::swap(eigenvectors[0], eigenvectors[2]);
- }
- if (eigenvalues[1] < eigenvalues[3])
- {
- std::swap(eigenvalues[1], eigenvalues[3]);
- std::swap(eigenvectors[1], eigenvectors[3]);
- }
- if (eigenvalues[0] < eigenvalues[1])
- {
- std::swap(eigenvalues[0], eigenvalues[1]);
- std::swap(eigenvectors[0], eigenvectors[1]);
- }
- if (eigenvalues[2] < eigenvalues[3])
- {
- std::swap(eigenvalues[2], eigenvalues[3]);
- std::swap(eigenvectors[2], eigenvectors[3]);
- }
- if (eigenvalues[1] < eigenvalues[2])
- {
- std::swap(eigenvalues[1], eigenvalues[2]);
- std::swap(eigenvectors[1], eigenvectors[2]);
- }
- }
-
-}//namespace glm
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-10-06 01:40:58 +0000