1 #ifndef VIENNACL_LINALG_TQL2_HPP
2 #define VIENNACL_LINALG_TQL2_HPP
41 template <
typename SCALARTYPE,
typename VectorType,
typename F>
49 std::vector<SCALARTYPE> cs(n), ss(n);
59 SCALARTYPE eps =
static_cast<SCALARTYPE
>(viennacl::linalg::detail::EPS);
64 tst1 = std::max<SCALARTYPE>(tst1, std::fabs(d[l]) + std::fabs(e[l]));
68 if (std::fabs(e[m]) <= eps * tst1)
83 SCALARTYPE p = (d[l + 1] - g) / (2 * e[l]);
84 SCALARTYPE r = viennacl::linalg::detail::pythag<SCALARTYPE>(p, 1);
90 d[l] = e[l] / (p + r);
91 d[l + 1] = e[l] * (p + r);
92 SCALARTYPE dl1 = d[l + 1];
93 SCALARTYPE h = g - d[l];
106 SCALARTYPE el1 = e[l + 1];
109 for (
int i2 =
int(m) - 1; i2 >= int(l); i2--)
121 p = c * d[i] - s * g;
122 d[i + 1] = h + s * (c * g + s * d[i]);
130 p = -s * s2 * c3 * el1 * e[l] / dl1;
141 while (std::fabs(e[l]) > eps * tst1);
Generic interface for matrix-vector and matrix-matrix products. See viennacl/linalg/vector_operations...
Implementation of the dense matrix class.
vcl_size_t size1(MatrixType const &mat)
Generic routine for obtaining the number of rows of a matrix (ViennaCL, uBLAS, etc.)
void tql2(matrix_base< SCALARTYPE, F > &Q, VectorType &d, VectorType &e)
viennacl::scalar< int > s2
Common routines used for the QR method and SVD. Experimental.
SCALARTYPE pythag(SCALARTYPE a, SCALARTYPE b)
The vector type with operator-overloads and proxy classes is defined here. Linear algebra operations ...
void copy(std::vector< NumericT > &cpu_vec, circulant_matrix< NumericT, AlignmentV > &gpu_mat)
Copies a circulant matrix from the std::vector to the OpenCL device (either GPU or multi-core CPU) ...
void givens_next(matrix_base< NumericT > &Q, vector_base< NumericT > &tmp1, vector_base< NumericT > &tmp2, int l, int m)
This function updates the matrix Q. It is part of the tql2 algorithm.