blas/double.cpp

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2009 Gael Guennebaud <gael.guennebaud@inria.fr>
// 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/.

#define SCALAR double
#define SCALAR_SUFFIX d
#define SCALAR_SUFFIX_UP "D"
#define ISCOMPLEX 0

#include "level1_impl.h"
#include "level1_real_impl.h"
#include "level2_impl.h"
#include "level2_real_impl.h"
#include "level3_impl.h"

double EIGEN_BLAS_FUNC(sdot)(int* n, float* x, int* incx, float* y, int* incy) {
  if (*n <= 0) return 0;

  if (*incx == 1 && *incy == 1)
    return (make_vector(x, *n).cast<double>().cwiseProduct(make_vector(y, *n).cast<double>())).sum();
  else if (*incx > 0 && *incy > 0)
    return (make_vector(x, *n, *incx).cast<double>().cwiseProduct(make_vector(y, *n, *incy).cast<double>())).sum();
  else if (*incx < 0 && *incy > 0)
    return (make_vector(x, *n, -*incx).reverse().cast<double>().cwiseProduct(make_vector(y, *n, *incy).cast<double>()))
        .sum();
  else if (*incx > 0 && *incy < 0)
    return (make_vector(x, *n, *incx).cast<double>().cwiseProduct(make_vector(y, *n, -*incy).reverse().cast<double>()))
        .sum();
  else if (*incx < 0 && *incy < 0)
    return (make_vector(x, *n, -*incx)
                .reverse()
                .cast<double>()
                .cwiseProduct(make_vector(y, *n, -*incy).reverse().cast<double>()))
        .sum();
  else
    return 0;
}