Server : Apache/2.4.41 (Ubuntu) System : Linux absol.cf 5.4.0-198-generic #218-Ubuntu SMP Fri Sep 27 20:18:53 UTC 2024 x86_64 User : www-data ( 33) PHP Version : 7.4.33 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_get_handler,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,pcntl_async_signals,pcntl_unshare, Directory :  /usr/include/boost/graph/

Upload File : current_dir [ Writeable ] document_root [ Writeable ]

// Copyright 2004 The Trustees of Indiana University.

// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

//  Authors: Douglas Gregor
//           Andrew Lumsdaine
#ifndef BOOST_GRAPH_CIRCLE_LAYOUT_HPP
#define BOOST_GRAPH_CIRCLE_LAYOUT_HPP
#include <boost/config/no_tr1/cmath.hpp>
#include <boost/math/constants/constants.hpp>
#include <utility>
#include <boost/graph/graph_traits.hpp>
#include <boost/graph/iteration_macros.hpp>
#include <boost/graph/topology.hpp>
#include <boost/static_assert.hpp>

namespace boost {
  /** 
   * \brief Layout the graph with the vertices at the points of a regular
   * n-polygon. 
   *
   * The distance from the center of the polygon to each point is
   * determined by the @p radius parameter. The @p position parameter
   * must be an Lvalue Property Map whose value type is a class type
   * containing @c x and @c y members that will be set to the @c x and
   * @c y coordinates.
   */
  template<typename VertexListGraph, typename PositionMap, typename Radius>
  void 
  circle_graph_layout(const VertexListGraph& g, PositionMap position,
                      Radius radius)
  {
    BOOST_STATIC_ASSERT (property_traits<PositionMap>::value_type::dimensions >= 2);
    const double pi = boost::math::constants::pi<double>();

#ifndef BOOST_NO_STDC_NAMESPACE
    using std::sin;
    using std::cos;
#endif // BOOST_NO_STDC_NAMESPACE

    typedef typename graph_traits<VertexListGraph>::vertices_size_type 
      vertices_size_type;

    vertices_size_type n = num_vertices(g);
    
    vertices_size_type i = 0;
    double two_pi_over_n = 2. * pi / n;
    BGL_FORALL_VERTICES_T(v, g, VertexListGraph) {
      position[v][0] = radius * cos(i * two_pi_over_n);
      position[v][1] = radius * sin(i * two_pi_over_n);
      ++i;
    }
  }
} // end namespace boost

#endif // BOOST_GRAPH_CIRCLE_LAYOUT_HPP