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Diffstat (limited to 'eigen/blas/Rank2Update.h')
-rw-r--r-- | eigen/blas/Rank2Update.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/eigen/blas/Rank2Update.h b/eigen/blas/Rank2Update.h new file mode 100644 index 0000000..138d70f --- /dev/null +++ b/eigen/blas/Rank2Update.h @@ -0,0 +1,57 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2012 Chen-Pang He <jdh8@ms63.hinet.net> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef EIGEN_RANK2UPDATE_H +#define EIGEN_RANK2UPDATE_H + +namespace internal { + +/* Optimized selfadjoint matrix += alpha * uv' + conj(alpha)*vu' + * This is the low-level version of SelfadjointRank2Update.h + */ +template<typename Scalar, typename Index, int UpLo> +struct rank2_update_selector +{ + static void run(Index size, Scalar* mat, Index stride, const Scalar* u, const Scalar* v, Scalar alpha) + { + typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap; + for (Index i=0; i<size; ++i) + { + Map<Matrix<Scalar,Dynamic,1> >(mat+stride*i+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)) += + numext::conj(alpha) * numext::conj(u[i]) * OtherMap(v+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)) + + alpha * numext::conj(v[i]) * OtherMap(u+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)); + } + } +}; + +/* Optimized selfadjoint matrix += alpha * uv' + conj(alpha)*vu' + * The matrix is in packed form. + */ +template<typename Scalar, typename Index, int UpLo> +struct packed_rank2_update_selector +{ + static void run(Index size, Scalar* mat, const Scalar* u, const Scalar* v, Scalar alpha) + { + typedef Map<const Matrix<Scalar,Dynamic,1> > OtherMap; + Index offset = 0; + for (Index i=0; i<size; ++i) + { + Map<Matrix<Scalar,Dynamic,1> >(mat+offset, UpLo==Lower ? size-i : (i+1)) += + numext::conj(alpha) * numext::conj(u[i]) * OtherMap(v+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)) + + alpha * numext::conj(v[i]) * OtherMap(u+(UpLo==Lower ? i : 0), UpLo==Lower ? size-i : (i+1)); + //FIXME This should be handled outside. + mat[offset+(UpLo==Lower ? 0 : i)] = numext::real(mat[offset+(UpLo==Lower ? 0 : i)]); + offset += UpLo==Lower ? size-i : (i+1); + } + } +}; + +} // end namespace internal + +#endif // EIGEN_RANK2UPDATE_H |