Edit: /usr/include/boost/graph/metis.hpp (10982B)
// Copyright 2005 The Trustees of Indiana University.
// Use, modification and distribution is subject to 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_METIS_HPP
#define BOOST_GRAPH_METIS_HPP
#ifdef BOOST_GRAPH_METIS_NO_INLINE
#define BOOST_GRAPH_METIS_INLINE_KEYWORD
#else
#define BOOST_GRAPH_METIS_INLINE_KEYWORD inline
#endif
#include
#include
#include
#include
#include
#include
#include
#include
namespace boost
{
namespace graph
{
class BOOST_SYMBOL_VISIBLE metis_exception : public std::exception
{
};
class BOOST_SYMBOL_VISIBLE metis_input_exception : public metis_exception
{
};
class metis_reader
{
public:
typedef std::size_t vertices_size_type;
typedef std::size_t edges_size_type;
typedef double vertex_weight_type;
typedef double edge_weight_type;
class edge_iterator
{
public:
typedef std::input_iterator_tag iterator_category;
typedef std::pair< vertices_size_type, vertices_size_type >
value_type;
typedef const value_type& reference;
typedef const value_type* pointer;
typedef std::ptrdiff_t difference_type;
private:
class postincrement_proxy
{
postincrement_proxy(const value_type& value) : value(value) {}
public:
reference operator*() const { return value; }
private:
value_type value;
friend class edge_iterator;
};
public:
edge_iterator& operator++();
postincrement_proxy operator++(int);
reference operator*() const { return self->edge; }
pointer operator->() const { return &self->edge; }
// Default copy constructor and assignment operator are okay
private:
edge_iterator(metis_reader* self);
void advance(bool skip_initial_read);
metis_reader* self;
friend class metis_reader;
friend bool operator==(edge_iterator, edge_iterator);
friend bool operator!=(edge_iterator, edge_iterator);
};
friend class edge_iterator;
class edge_weight_iterator
{
public:
typedef std::input_iterator_tag iterator_category;
typedef edge_weight_type value_type;
typedef const value_type& reference;
typedef const value_type* pointer;
// Default copy constructor and assignment operator are okay
reference operator*() const { return self->edge_weight; }
pointer operator->() const { return &self->edge_weight; }
edge_weight_iterator& operator++() { return *this; }
edge_weight_iterator operator++(int) { return *this; }
private:
edge_weight_iterator(metis_reader* self) : self(self) {}
metis_reader* self;
friend class metis_reader;
};
metis_reader(std::istream& in) : in(in), edge_weight(1.0) { start(); }
edge_iterator begin();
edge_iterator end();
edge_weight_iterator weight_begin();
vertices_size_type num_vertices() const { return n_vertices; }
edges_size_type num_edges() const { return n_edges; }
std::size_t num_vertex_weights() const { return n_vertex_weights; }
vertex_weight_type vertex_weight(vertices_size_type v, std::size_t n)
{
return vertex_weights[v * num_vertex_weights() + n];
}
bool has_edge_weights() const { return edge_weights; }
private:
void start();
// Configuration information
std::istream& in;
// Information about the current METIS file
vertices_size_type n_vertices;
edges_size_type n_edges;
std::size_t n_vertex_weights;
bool edge_weights;
// Information about the current edge/vertex
std::istringstream line_in;
std::pair< vertices_size_type, vertices_size_type > edge;
std::vector< vertex_weight_type > vertex_weights;
edge_weight_type edge_weight;
friend bool operator==(edge_iterator, edge_iterator);
friend bool operator!=(edge_iterator, edge_iterator);
};
class metis_distribution
{
public:
typedef int process_id_type;
typedef std::size_t size_type;
typedef std::vector< process_id_type >::iterator iterator;
metis_distribution(std::istream& in, process_id_type my_id);
size_type block_size(process_id_type id, size_type) const;
process_id_type operator()(size_type n) const { return vertices[n]; }
size_type local(size_type n) const;
size_type global(size_type n) const { return global(my_id, n); }
size_type global(process_id_type id, size_type n) const;
iterator begin() { return vertices.begin(); }
iterator end() { return vertices.end(); }
private:
process_id_type my_id;
std::vector< process_id_type > vertices;
};
#if !defined(BOOST_GRAPH_METIS_NO_INLINE) || defined(BOOST_GRAPH_METIS_SOURCE)
BOOST_GRAPH_METIS_INLINE_KEYWORD
bool operator==(
metis_reader::edge_iterator x, metis_reader::edge_iterator y)
{
return (x.self == y.self
|| (x.self && x.self->edge.first == x.self->num_vertices())
|| (y.self && y.self->edge.first == y.self->num_vertices()));
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
bool operator!=(
metis_reader::edge_iterator x, metis_reader::edge_iterator y)
{
return !(x == y);
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_iterator::edge_iterator(metis_reader* self) : self(self)
{
if (self)
advance(true);
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_iterator& metis_reader::edge_iterator::operator++()
{
advance(false);
return *this;
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
void metis_reader::edge_iterator::advance(bool skip_initial_read)
{
do
{
if (!skip_initial_read)
{
// Try to read the next edge
if (self->line_in >> std::ws >> self->edge.second)
{
--self->edge.second;
if (self->has_edge_weights())
{
if (!(self->line_in >> self->edge_weight))
boost::throw_exception(metis_input_exception());
}
return;
}
// Check if we're done
++self->edge.first;
if (self->edge.first == self->num_vertices())
return;
}
// Find the next line
std::string line;
while (getline(self->in, line) && !line.empty() && line[0] == '%')
{
/* Keep reading lines in the loop header... */
}
if (!self->in)
boost::throw_exception(metis_input_exception());
self->line_in.str(line);
self->line_in.clear();
// Read the next line
std::size_t weights_left = self->n_vertex_weights;
vertex_weight_type weight;
while (weights_left > 0)
{
if (self->line_in >> weight)
self->vertex_weights.push_back(weight);
else
boost::throw_exception(metis_input_exception());
--weights_left;
}
// Successive iterations will pick up edges for this vertex.
skip_initial_read = false;
} while (true);
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_iterator::postincrement_proxy
metis_reader::edge_iterator::operator++(int)
{
postincrement_proxy result(**this);
++(*this);
return result;
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_iterator metis_reader::begin()
{
if (edge.first != 0)
start();
return edge_iterator(this);
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_iterator metis_reader::end() { return edge_iterator(0); }
BOOST_GRAPH_METIS_INLINE_KEYWORD
metis_reader::edge_weight_iterator metis_reader::weight_begin()
{
return edge_weight_iterator(this);
}
BOOST_GRAPH_METIS_INLINE_KEYWORD
void metis_reader::start()
{
in.seekg(0, std::ios::beg);
std::string line;
while (getline(in, line) && !line.empty() && line[0] == '%')
{
/* Keep getting lines in loop header. */
}
if (!in || line.empty())
boost::throw_exception(metis_input_exception());
// Determine number of vertices and edges in the graph
line_in.str(line);
if (!(line_in >> n_vertices >> n_edges))
boost::throw_exception(metis_input_exception());
// Determine whether vertex or edge weights are included in the graph
int fmt = 0;
line_in >> fmt;
n_vertex_weights = fmt / 10;
edge_weights = (fmt % 10 == 1);
// Determine how many (if any!) vertex weights are included
if (n_vertex_weights)
line_in >> n_vertex_weights;
// Setup the iteration data structures
edge_weight = 1.0;
edge.first = 0;
edge.second = 0;
vertex_weights.reserve(n_vertex_weights * num_vertices());
}
metis_distribution::metis_distribution(
std::istream& in, process_id_type my_id)
: my_id(my_id)
, vertices(std::istream_iterator< process_id_type >(in),
std::istream_iterator< process_id_type >())
{
}
metis_distribution::size_type metis_distribution::block_size(
process_id_type id, size_type) const
{
return std::count(vertices.begin(), vertices.end(), id);
}
metis_distribution::size_type metis_distribution::local(size_type n) const
{
return std::count(vertices.begin(), vertices.begin() + n, vertices[n]);
}
metis_distribution::size_type metis_distribution::global(
process_id_type id, size_type n) const
{
std::vector< process_id_type >::const_iterator i = vertices.begin();
while (*i != id)
++i;
while (n > 0)
{
do
{
++i;
} while (*i != id);
--n;
}
return i - vertices.begin();
}
#endif
}
} // end namespace boost::graph
#endif // BOOST_GRAPH_METIS_HPP