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116 lines
4.2 KiB
C
116 lines
4.2 KiB
C
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// This file is part of Eigen, a lightweight C++ template library
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// for linear algebra.
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//
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// Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
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//
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// Eigen is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 3 of the License, or (at your option) any later version.
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//
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// Alternatively, you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of
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// the License, or (at your option) any later version.
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//
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// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public
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// License and a copy of the GNU General Public License along with
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// Eigen. If not, see <http://www.gnu.org/licenses/>.
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#include "common.h"
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// computes the sum of magnitudes of all vector elements or, for a complex vector x, the sum
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// res = |Rex1| + |Imx1| + |Rex2| + |Imx2| + ... + |Rexn| + |Imxn|, where x is a vector of order n
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RealScalar EIGEN_BLAS_FUNC(asum)(int *n, RealScalar *px, int *incx)
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{
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// std::cerr << "_asum " << *n << " " << *incx << "\n";
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Scalar* x = reinterpret_cast<Scalar*>(px);
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if(*n<=0) return 0;
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if(*incx==1) return vector(x,*n).cwiseAbs().sum();
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else return vector(x,*n,std::abs(*incx)).cwiseAbs().sum();
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}
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// computes a vector-vector dot product.
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Scalar EIGEN_BLAS_FUNC(dot)(int *n, RealScalar *px, int *incx, RealScalar *py, int *incy)
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{
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// std::cerr << "_dot " << *n << " " << *incx << " " << *incy << "\n";
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if(*n<=0) return 0;
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Scalar* x = reinterpret_cast<Scalar*>(px);
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Scalar* y = reinterpret_cast<Scalar*>(py);
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if(*incx==1 && *incy==1) return (vector(x,*n).cwiseProduct(vector(y,*n))).sum();
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else if(*incx>0 && *incy>0) return (vector(x,*n,*incx).cwiseProduct(vector(y,*n,*incy))).sum();
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else if(*incx<0 && *incy>0) return (vector(x,*n,-*incx).reverse().cwiseProduct(vector(y,*n,*incy))).sum();
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else if(*incx>0 && *incy<0) return (vector(x,*n,*incx).cwiseProduct(vector(y,*n,-*incy).reverse())).sum();
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else if(*incx<0 && *incy<0) return (vector(x,*n,-*incx).reverse().cwiseProduct(vector(y,*n,-*incy).reverse())).sum();
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else return 0;
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}
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// computes the Euclidean norm of a vector.
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// FIXME
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Scalar EIGEN_BLAS_FUNC(nrm2)(int *n, RealScalar *px, int *incx)
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{
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// std::cerr << "_nrm2 " << *n << " " << *incx << "\n";
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if(*n<=0) return 0;
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Scalar* x = reinterpret_cast<Scalar*>(px);
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if(*incx==1) return vector(x,*n).stableNorm();
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else return vector(x,*n,std::abs(*incx)).stableNorm();
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}
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int EIGEN_BLAS_FUNC(rot)(int *n, RealScalar *px, int *incx, RealScalar *py, int *incy, RealScalar *pc, RealScalar *ps)
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{
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// std::cerr << "_rot " << *n << " " << *incx << " " << *incy << "\n";
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if(*n<=0) return 0;
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Scalar* x = reinterpret_cast<Scalar*>(px);
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Scalar* y = reinterpret_cast<Scalar*>(py);
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Scalar c = *reinterpret_cast<Scalar*>(pc);
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Scalar s = *reinterpret_cast<Scalar*>(ps);
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StridedVectorType vx(vector(x,*n,std::abs(*incx)));
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StridedVectorType vy(vector(y,*n,std::abs(*incy)));
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Reverse<StridedVectorType> rvx(vx);
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Reverse<StridedVectorType> rvy(vy);
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if(*incx<0 && *incy>0) internal::apply_rotation_in_the_plane(rvx, vy, JacobiRotation<Scalar>(c,s));
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else if(*incx>0 && *incy<0) internal::apply_rotation_in_the_plane(vx, rvy, JacobiRotation<Scalar>(c,s));
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else internal::apply_rotation_in_the_plane(vx, vy, JacobiRotation<Scalar>(c,s));
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return 0;
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}
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/*
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// performs rotation of points in the modified plane.
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int EIGEN_BLAS_FUNC(rotm)(int *n, RealScalar *px, int *incx, RealScalar *py, int *incy, RealScalar *param)
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{
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Scalar* x = reinterpret_cast<Scalar*>(px);
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Scalar* y = reinterpret_cast<Scalar*>(py);
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// TODO
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return 0;
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}
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// computes the modified parameters for a Givens rotation.
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int EIGEN_BLAS_FUNC(rotmg)(RealScalar *d1, RealScalar *d2, RealScalar *x1, RealScalar *x2, RealScalar *param)
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{
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// TODO
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return 0;
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}
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*/
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