Unable to use integer edge weights with Kamada-Kawai layout - c++

Question

The question started here, but after all the updates it is already a different question with a different title.
My Graph type is defined as follows:
using Graph = boost::adjacency_list<vecS, setS, undirectedS, State, CostType>;
where CostType happens to be int.
I am trying to obtain the Kamada-Kawai spring layout as follows:
template <class PointMap>
PointMap layout() const {
PointMap res;
boost::associative_property_map<PointMap> temp(res);
circle_graph_layout(g_, temp, 10.0);
// https://stackoverflow.com/q/33903879/2725810
// https://stackoverflow.com/a/8555715/2725810
typedef std::map<VertexDescriptor, std::size_t> IndexMap;
IndexMap mapIndex;
associative_property_map<IndexMap> propmapIndex(mapIndex);
// http://www.boost.org/doc/libs/1_59_0/libs/graph/doc/bundles.html
kamada_kawai_spring_layout(g_, temp, get(edge_bundle, g_),
square_topology<>(50.0), side_length(50.0),
layout_tolerance<CostType>(),
CostType(1), propmapIndex);
return res;
}
gcc version 4.8.2 complains:
In file included from Graph.h:13:0,
from Astar.h:5,
from Test.cpp:4:
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp: In instantiation of ‘bool boost::detail::graph::kamada_kawai_spring_layout_impl<Topology, Graph, PositionMap, WeightMap, EdgeOrSideLength, Done, VertexIndexMap, DistanceMatrix, SpringStrengthMatrix, PartialDerivativeMap>::run() [with Topology = boost::square_topology<>; Graph = boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>; PositionMap = boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >; WeightMap = boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>; EdgeOrSideLength = boost::detail::graph::edge_or_side<false, double>; Done = boost::layout_tolerance<int>; VertexIndexMap = boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >; DistanceMatrix = __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >; SpringStrengthMatrix = __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >; PartialDerivativeMap = boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::convex_topology<2ul>::point_difference*, std::vector<boost::convex_topology<2ul>::point_difference, std::allocator<boost::convex_topology<2ul>::point_difference> > >, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, boost::convex_topology<2ul>::point_difference, boost::convex_topology<2ul>::point_difference&>]’:
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:524:20: required from ‘bool boost::kamada_kawai_spring_layout(const Graph&, PositionMap, WeightMap, const Topology&, boost::detail::graph::edge_or_side<EdgeOrSideLength, T>, Done, typename boost::property_traits<DistanceMap>::value_type, VertexIndexMap, DistanceMatrix, SpringStrengthMatrix, PartialDerivativeMap) [with Topology = boost::square_topology<>; Graph = boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>; PositionMap = boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >; WeightMap = boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>; T = double; bool EdgeOrSideLength = false; Done = boost::layout_tolerance<int>; VertexIndexMap = boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >; DistanceMatrix = __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >; SpringStrengthMatrix = __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >; PartialDerivativeMap = boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::convex_topology<2ul>::point_difference*, std::vector<boost::convex_topology<2ul>::point_difference, std::allocator<boost::convex_topology<2ul>::point_difference> > >, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, boost::convex_topology<2ul>::point_difference, boost::convex_topology<2ul>::point_difference&>; typename boost::property_traits<DistanceMap>::value_type = int]’
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:559:79: required from ‘bool boost::kamada_kawai_spring_layout(const Graph&, PositionMap, WeightMap, const Topology&, boost::detail::graph::edge_or_side<EdgeOrSideLength, T>, Done, typename boost::property_traits<DistanceMap>::value_type, VertexIndexMap) [with Topology = boost::square_topology<>; Graph = boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>; PositionMap = boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >; WeightMap = boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>; T = double; bool EdgeOrSideLength = false; Done = boost::layout_tolerance<int>; VertexIndexMap = boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >; typename boost::property_traits<DistanceMap>::value_type = int]’
Graph.h:112:61: required from ‘PointMap StateGraph<StateNeighbor>::layout() const [with PointMap = std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > >; StateNeighbor = StateNeighbor<Pancake>]’
Drawer.h:60:75: required from ‘Drawer<Graph>::Drawer(const Graph&) [with Graph = StateGraph<StateNeighbor<Pancake> >]’
Test.cpp:34:22: required from here
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:313:96: error: no matching function for call to ‘boost::detail::graph::linear_solver<2ul>::solve(boost::detail::graph::kamada_kawai_spring_layout_impl<boost::square_topology<>, boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>, boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >, boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>, boost::detail::graph::edge_or_side<false, double>, boost::layout_tolerance<int>, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::convex_topology<2ul>::point_difference*, std::vector<boost::convex_topology<2ul>::point_difference, std::allocator<boost::convex_topology<2ul>::point_difference> > >, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, boost::convex_topology<2ul>::point_difference, boost::convex_topology<2ul>::point_difference&> >::weight_type [2][2], boost::detail::graph::kamada_kawai_spring_layout_impl<boost::square_topology<>, boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>, boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >, boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>, boost::detail::graph::edge_or_side<false, double>, boost::layout_tolerance<int>, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::convex_topology<2ul>::point_difference*, std::vector<boost::convex_topology<2ul>::point_difference, std::allocator<boost::convex_topology<2ul>::point_difference> > >, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, boost::convex_topology<2ul>::point_difference, boost::convex_topology<2ul>::point_difference&> >::deriv_type&)’
_difference_type delta = -linear_solver<Point::dimensions>::solve(dE_d_d, dE_d);
^
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:313:96: note: candidate is:
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:95:18: note: template<class Vec> static Vec boost::detail::graph::linear_solver<2ul>::solve(double (*)[2], Vec)
static Vec solve(double mat[2][2], Vec rhs) {
^
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:95:18: note: template argument deduction/substitution failed:
/home/meir/boost_1_59_0/boost/graph/kamada_kawai_spring_layout.hpp:313:96: note: cannot convert ‘dE_d_d’ (type ‘boost::detail::graph::kamada_kawai_spring_layout_impl<boost::square_topology<>, boost::adjacency_list<boost::vecS, boost::setS, boost::undirectedS, Pancake, int, boost::no_property, boost::listS>, boost::associative_property_map<std::map<void*, boost::convex_topology<2ul>::point, std::less<void*>, std::allocator<std::pair<void* const, boost::convex_topology<2ul>::point> > > >, boost::adj_list_edge_property_map<boost::undirected_tag, int, const int&, void*, const int, boost::edge_bundle_t>, boost::detail::graph::edge_or_side<false, double>, boost::layout_tolerance<int>, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, __gnu_cxx::__normal_iterator<std::vector<int>*, std::vector<std::vector<int>, std::allocator<std::vector<int> > > >, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::convex_topology<2ul>::point_difference*, std::vector<boost::convex_topology<2ul>::point_difference, std::allocator<boost::convex_topology<2ul>::point_difference> > >, boost::associative_property_map<std::map<void*, long unsigned int, std::less<void*>, std::allocator<std::pair<void* const, long unsigned int> > > >, boost::convex_topology<2ul>::point_difference, boost::convex_topology<2ul>::point_difference&> >::weight_type [2][2] {aka int [2][2]}’) to type ‘double (*)[2]’
_difference_type delta = -linear_solver<Point::dimensions>::solve(dE_d_d, dE_d);
This message is too cryptic for me to understand. It has something to do with not being able to convert int [2][2] to double (*)[2]. Is this related to the fact that CostType is int? But why can't it be? I will very much appreciate help in understanding what I am doing wrong.

Answer 1

Indeed, the error indicates the weights must be doubles.
That's because the algorithm invokes a linear solver with the raw points, and that's failing because the weight type is not a real number type.
If you change
using CostType = double;
everything compiles fine. Live On Coliru
If you insist, you can use a transformation:
#include <boost/property_map/transform_value_property_map.hpp>
kamada_kawai_spring_layout(g_, temp,
boost::make_transform_value_property_map([](int i) -> double { return i; }, get(edge_bundle, g_)),
square_topology<>(50.0),
side_length(50.0),
layout_tolerance<double>(),
double(1),
propmapIndex);
If you don't want to use the lambda, use a functor:
struct to_double { double operator()(int i) const { return i; } };
kamada_kawai_spring_layout(g_, temp,
boost::make_transform_value_property_map(to_double(), get(edge_bundle, g_)),
square_topology<>(50.0),
side_length(50.0),
layout_tolerance<double>(),
double(1),
propmapIndex);