ger.hpp

Go to the documentation of this file.

// Copyright (c) 2019--present, The Simons Foundation
// This file is part of TRIQS/nda and is licensed under the Apache License, Version 2.0.
// SPDX-License-Identifier: Apache-2.0
// See LICENSE in the root of this distribution for details.

 
#pragma once
 
#include "./interface/cxx_interface.hpp"
#include "./tools.hpp"
#include "../concepts.hpp"
#include "../layout_transforms.hpp"
#include "../layout/policies.hpp"
#include "../macros.hpp"
#include "../mem/address_space.hpp"
#include "../traits.hpp"
 
#ifndef NDA_HAVE_DEVICE
#include "../device.hpp"
#endif // NDA_HAVE_DEVICE
 
namespace nda::blas {


  template <MemoryVector X, MemoryVector Y, MemoryMatrix M>
    requires(have_same_value_type_v<X, Y, M> and mem::have_compatible_addr_space<X, Y, M> and is_blas_lapack_v<get_value_t<X>>)
  void ger(get_value_t<X> alpha, X const &x, Y const &y, M &&m) { // NOLINT (temporary views are allowed here)
    // for C-layout arrays/views, call ger with the transpose and swap x and y
    if constexpr (has_C_layout<M>) {
      ger(alpha, y, x, transpose(m));
      return;
    }
 
    // check the dimensions of the input/output arrays/views
    EXPECTS(m.extent(0) == x.size());
    EXPECTS(m.extent(1) == y.size());
 
    // arrays/views must be BLAS compatible
    EXPECTS(m.indexmap().min_stride() == 1);
 
    // perform actual library call
    if constexpr (mem::have_device_compatible_addr_space<X, Y, M>) {
#if defined(NDA_HAVE_DEVICE)
      device::ger(m.extent(0), m.extent(1), alpha, x.data(), x.indexmap().strides()[0], y.data(), y.indexmap().strides()[0], m.data(), get_ld(m));
#else
      compile_error_no_gpu();
#endif
    } else {
      f77::ger(m.extent(0), m.extent(1), alpha, x.data(), x.indexmap().strides()[0], y.data(), y.indexmap().strides()[0], m.data(), get_ld(m));
    }
  }

 
} // namespace nda::blas