Constant.h

// Copyright (C) 2019-2021 Chris Richardson, Michal Habera and Garth N.
// Wells
//
// This file is part of DOLFINx (https://www.fenicsproject.org)
//
// SPDX-License-Identifier:    LGPL-3.0-or-later
 
#pragma once
 
#include <type_traits>
#include <vector>
#include <xtensor/xarray.hpp>
 
namespace dolfinx::fem
{
 
template <typename T>
class Constant
{
public:
  template <
      typename = std::enable_if_t<
          std::is_arithmetic_v<
              T> || std::is_same_v<T, std::complex<float>> || std::is_same_v<T, std::complex<double>>>>
  Constant(T c) : value({c})
  {
  }
 
  Constant(const xt::xarray<T>& c)
      : shape(c.shape().begin(), c.shape().end()), value(c.begin(), c.end())
  {
  }
 
  std::vector<int> shape;
 
  std::vector<T> value;
};
} // namespace dolfinx::fem