void mitk::ConnectomicsSimulatedAnnealingPermutationModularity::permutateMappingSingleNodeShift(
ToModuleMapType *vertexToModuleMap, mitk::ConnectomicsNetwork::Pointer network )
{
const int nodeCount = vertexToModuleMap->size();
const int moduleCount = getNumberOfModules( vertexToModuleMap );
// the random number generators
vnl_random rng( (unsigned int) rand() );
unsigned long randomNode = rng.lrand32( nodeCount - 1 );
// move the node either to any existing module, or to its own
//unsigned long randomModule = rng.lrand32( moduleCount );
unsigned long randomModule = rng.lrand32( moduleCount - 1 );
// do some sanity checks
if ( nodeCount < 2 )
{
// no sense in doing anything
return;
}
const std::vector< VertexDescriptorType > allNodesVector
= network->GetVectorOfAllVertexDescriptors();
ToModuleMapType::iterator iter = vertexToModuleMap->find( allNodesVector[ randomNode ] );
const int previousModuleNumber = iter->second;
// if we move the node to its own module, do nothing
if( previousModuleNumber == (long)randomModule )
{
return;
}
iter->second = randomModule;
if( getNumberOfVerticesInModule( vertexToModuleMap, previousModuleNumber ) < 1 )
{
removeModule( vertexToModuleMap, previousModuleNumber );
}
}
void mitk::ConnectomicsSyntheticNetworkGenerator::GenerateSyntheticRandomNetwork(
mitk::ConnectomicsNetwork::Pointer network, int numberOfPoints, double threshold )
{
// as the surface is proportional to the square of the radius the density stays the same
double radius = 5 * std::sqrt( (float) numberOfPoints );
//the random number generators
unsigned int randomOne = (unsigned int) rand();
unsigned int randomTwo = (unsigned int) rand();
vnl_random rng( (unsigned int) rand() );
vnl_random rng2( (unsigned int) rand() );
// map for storing the conversion from indices to vertex descriptor
std::map< int, mitk::ConnectomicsNetwork::VertexDescriptorType > idToVertexMap;
//add vertices on sphere surface
for( int loopID( 0 ); loopID < numberOfPoints; loopID++ )
{
std::vector< float > position;
std::string label;
std::stringstream labelStream;
labelStream << loopID;
label = labelStream.str();
//generate random, uniformly distributed points on a sphere surface
const double uVariable = rng.drand64( 0.0 , 1.0);
const double vVariable = rng.drand64( 0.0 , 1.0);
const double phi = 2 * vnl_math::pi * uVariable;
const double theta = std::acos( 2 * vVariable - 1 );
double xpos = radius * std::cos( phi ) * std::sin( theta );
double ypos = radius * std::sin( phi ) * std::sin( theta );
double zpos = radius * std::cos( theta );
position.push_back( xpos );
position.push_back( ypos );
position.push_back( zpos );
mitk::ConnectomicsNetwork::VertexDescriptorType newVertex = network->AddVertex( loopID );
network->SetLabel( newVertex, label );
network->SetCoordinates( newVertex, position );
if ( idToVertexMap.count( loopID ) > 0 )
{
MITK_ERROR << "Aborting network creation, duplicate vertex ID generated.";
m_LastGenerationWasSuccess = false;
return;
}
idToVertexMap.insert( std::pair< int, mitk::ConnectomicsNetwork::VertexDescriptorType >( loopID, newVertex) );
}
int edgeID(0);
// uniform weight of one
int edgeWeight(1);
mitk::ConnectomicsNetwork::VertexDescriptorType source;
mitk::ConnectomicsNetwork::VertexDescriptorType target;
for( int loopID( 0 ); loopID < numberOfPoints; loopID++ )
{
// to avoid creating an edge twice (this being an undirected graph) we only
// potentially generate edges with all nodes with a bigger ID
for( int innerLoopID( loopID ); innerLoopID < numberOfPoints; innerLoopID++ )
{
if( rng.drand64( 0.0 , 1.0) > threshold)
{
// do nothing
}
else
{
source = idToVertexMap.find( loopID )->second;
target = idToVertexMap.find( innerLoopID )->second;
network->AddEdge( source, target, loopID, innerLoopID, edgeWeight);
edgeID++;
}
} // end for( int innerLoopID( loopID ); innerLoopID < numberOfPoints; innerLoopID++ )
} // end for( int loopID( 0 ); loopID < numberOfPoints; loopID++ )
m_LastGenerationWasSuccess = true;
}
void mitk::ConnectomicsSyntheticNetworkGenerator::GenerateSyntheticCenterToSurfaceNetwork(
mitk::ConnectomicsNetwork::Pointer network, int numberOfPoints, double radius )
{
//the random number generators
unsigned int randomOne = (unsigned int) rand();
unsigned int randomTwo = (unsigned int) rand();
vnl_random rng( (unsigned int) rand() );
vnl_random rng2( (unsigned int) rand() );
mitk::ConnectomicsNetwork::VertexDescriptorType centerVertex;
int vertexID(0);
{ //add center vertex
std::vector< float > position;
std::string label;
std::stringstream labelStream;
labelStream << vertexID;
label = labelStream.str();
position.push_back( 0 );
position.push_back( 0 );
position.push_back( 0 );
centerVertex = network->AddVertex( vertexID );
network->SetLabel( centerVertex, label );
network->SetCoordinates( centerVertex, position );
}//end add center vertex
// uniform weight of one
int edgeWeight(1);
mitk::ConnectomicsNetwork::VertexDescriptorType source;
mitk::ConnectomicsNetwork::VertexDescriptorType target;
//add vertices on sphere surface
for( int loopID( 1 ); loopID < numberOfPoints; loopID++ )
{
std::vector< float > position;
std::string label;
std::stringstream labelStream;
labelStream << loopID;
label = labelStream.str();
//generate random, uniformly distributed points on a sphere surface
const double uVariable = rng.drand64( 0.0 , 1.0);
const double vVariable = rng.drand64( 0.0 , 1.0);
const double phi = 2 * vnl_math::pi * uVariable;
const double theta = std::acos( 2 * vVariable - 1 );
double xpos = radius * std::cos( phi ) * std::sin( theta );
double ypos = radius * std::sin( phi ) * std::sin( theta );
double zpos = radius * std::cos( theta );
position.push_back( xpos );
position.push_back( ypos );
position.push_back( zpos );
mitk::ConnectomicsNetwork::VertexDescriptorType newVertex = network->AddVertex( loopID );
network->SetLabel( newVertex, label );
network->SetCoordinates( newVertex, position );
network->AddEdge( newVertex, centerVertex, loopID, 0, edgeWeight);
}
m_LastGenerationWasSuccess = true;
}
void mitk::ConnectomicsSyntheticNetworkGenerator::GenerateSyntheticCubeNetwork(
mitk::ConnectomicsNetwork::Pointer network, int cubeExtent, double distance )
{
// map for storing the conversion from indices to vertex descriptor
std::map< int, mitk::ConnectomicsNetwork::VertexDescriptorType > idToVertexMap;
int vertexID(0);
for( int loopX( 0 ); loopX < cubeExtent; loopX++ )
{
for( int loopY( 0 ); loopY < cubeExtent; loopY++ )
{
for( int loopZ( 0 ); loopZ < cubeExtent; loopZ++ )
{
std::vector< float > position;
std::string label;
std::stringstream labelStream;
labelStream << vertexID;
label = labelStream.str();
position.push_back( loopX * distance );
position.push_back( loopY * distance );
position.push_back( loopZ * distance );
mitk::ConnectomicsNetwork::VertexDescriptorType newVertex = network->AddVertex( vertexID );
network->SetLabel( newVertex, label );
network->SetCoordinates( newVertex, position );
if ( idToVertexMap.count( vertexID ) > 0 )
{
MITK_ERROR << "Aborting network creation, duplicate vertex ID generated.";
m_LastGenerationWasSuccess = false;
return;
}
idToVertexMap.insert( std::pair< int, mitk::ConnectomicsNetwork::VertexDescriptorType >( vertexID, newVertex) );
vertexID++;
}
}
}
int edgeID(0), edgeSourceID(0), edgeTargetID(0);
// uniform weight of one
int edgeWeight(1);
mitk::ConnectomicsNetwork::VertexDescriptorType source;
mitk::ConnectomicsNetwork::VertexDescriptorType target;
for( int loopX( 0 ); loopX < cubeExtent; loopX++ )
{
for( int loopY( 0 ); loopY < cubeExtent; loopY++ )
{
for( int loopZ( 0 ); loopZ < cubeExtent; loopZ++ )
{
// to avoid creating an edge twice (this being an undirected graph) we only generate
// edges in three directions, the others will be supplied by the corresponding nodes
if( loopX != 0 )
{
edgeTargetID = edgeSourceID - cubeExtent * cubeExtent;
source = idToVertexMap.find( edgeSourceID )->second;
target = idToVertexMap.find( edgeTargetID )->second;
network->AddEdge( source, target, edgeSourceID, edgeTargetID, edgeWeight);
edgeID++;
}
if( loopY != 0 )
{
edgeTargetID = edgeSourceID - cubeExtent;
source = idToVertexMap.find( edgeSourceID )->second;
target = idToVertexMap.find( edgeTargetID )->second;
network->AddEdge( source, target, edgeSourceID, edgeTargetID, edgeWeight);
edgeID++;
}
if( loopZ != 0 )
{
edgeTargetID = edgeSourceID - 1;
source = idToVertexMap.find( edgeSourceID )->second;
target = idToVertexMap.find( edgeTargetID )->second;
network->AddEdge( source, target, edgeSourceID, edgeTargetID, edgeWeight);
edgeID++;
}
edgeSourceID++;
} // end for( int loopZ( 0 ); loopZ < cubeExtent; loopZ++ )
} // end for( int loopY( 0 ); loopY < cubeExtent; loopY++ )
} // end for( int loopX( 0 ); loopX < cubeExtent; loopX++ )
m_LastGenerationWasSuccess = true;
}
void mitk::ConnectomicsSimulatedAnnealingPermutationModularity::extractModuleSubgraph(
ToModuleMapType *vertexToModuleMap,
mitk::ConnectomicsNetwork::Pointer network,
int moduleToSplit,
mitk::ConnectomicsNetwork::Pointer subNetwork,
VertexToVertexMapType* graphToSubgraphVertexMap,
VertexToVertexMapType* subgraphToGraphVertexMap )
{
const std::vector< VertexDescriptorType > allNodesVector = network->GetVectorOfAllVertexDescriptors();
// add vertices to subgraph
for( unsigned int nodeNumber( 0 ); nodeNumber < allNodesVector.size() ; nodeNumber++)
{
if( moduleToSplit == vertexToModuleMap->find( allNodesVector[ nodeNumber ] )->second )
{
int id = network->GetNode( allNodesVector[ nodeNumber ] ).id;
VertexDescriptorType newVertex = subNetwork->AddVertex( id );
graphToSubgraphVertexMap->insert(
std::pair<VertexDescriptorType, VertexDescriptorType>(
allNodesVector[ nodeNumber ], newVertex
)
);
subgraphToGraphVertexMap->insert(
std::pair<VertexDescriptorType, VertexDescriptorType>(
newVertex, allNodesVector[ nodeNumber ]
)
);
}
}
// add edges to subgraph
VertexToVertexMapType::iterator iter = graphToSubgraphVertexMap->begin();
VertexToVertexMapType::iterator end = graphToSubgraphVertexMap->end();
while( iter != end )
{
const std::vector< VertexDescriptorType > adjacentNodexVector
= network->GetVectorOfAdjacentNodes( iter->first );
for( unsigned int adjacentNodeNumber( 0 ); adjacentNodeNumber < adjacentNodexVector.size() ; adjacentNodeNumber++)
{
// if the adjacent vertex is part of the subgraph,
// add edge, if it does not exist yet, else do nothing
VertexDescriptorType adjacentVertex = adjacentNodexVector[ adjacentNodeNumber ];
if( graphToSubgraphVertexMap->count( adjacentVertex ) > 0 )
{
if( !subNetwork->EdgeExists( iter->second, graphToSubgraphVertexMap->find( adjacentVertex )->second ) )
{ //edge exists in parent network, but not yet in sub network
const VertexDescriptorType vertexA = iter->second;
const VertexDescriptorType vertexB = graphToSubgraphVertexMap->find( adjacentVertex )->second;
const int sourceID = network->GetNode( vertexA ).id;
const int targetID = network->GetNode( vertexB ).id;
const int weight = network->GetEdge( iter->first, graphToSubgraphVertexMap->find( adjacentVertex )->first ).weight;
subNetwork->AddEdge( vertexA , vertexB, sourceID, targetID, weight );
}
}
}
iter++;
}// end while( iter != end )
}
double mitk::ConnectomicsSimulatedAnnealingCostFunctionModularity::CalculateModularity( mitk::ConnectomicsNetwork::Pointer network, ToModuleMapType* vertexToModuleMap ) const
{
double modularity( 0.0 );
int numberOfModules = getNumberOfModules( vertexToModuleMap );
if( network->GetNumberOfVertices() != vertexToModuleMap->size() )
{
MBI_ERROR << "Number of vertices and vertex to module map size do not match!";
return modularity;
}
int numberOfLinksInNetwork( 0 );
std::vector< int > numberOfLinksInModule, sumOfDegreesInModule;
numberOfLinksInModule.resize( numberOfModules, 0 );
sumOfDegreesInModule.resize( numberOfModules, 0 );
// get vector of all vertex descriptors in the network
const std::vector< VertexDescriptorType > allNodesVector
= network->GetVectorOfAllVertexDescriptors();
for( int nodeNumber( 0 ); nodeNumber < allNodesVector.size() ; nodeNumber++)
{
int correspondingModule = vertexToModuleMap->find( allNodesVector[ nodeNumber ] )->second;
const std::vector< VertexDescriptorType > adjacentNodexVector
= network->GetVectorOfAdjacentNodes( allNodesVector[ nodeNumber ] );
numberOfLinksInNetwork += adjacentNodexVector.size();
sumOfDegreesInModule[ correspondingModule ] += adjacentNodexVector.size();
for( int adjacentNodeNumber( 0 ); adjacentNodeNumber < adjacentNodexVector.size() ; adjacentNodeNumber++)
{
if( correspondingModule == vertexToModuleMap->find( adjacentNodexVector[ adjacentNodeNumber ] )->second )
{
numberOfLinksInModule[ correspondingModule ]++;
}
}
}
// the numbers for links have to be halved, as each edge was counted twice
numberOfLinksInNetwork = numberOfLinksInNetwork / 2;
// if the network contains no links return 0
if( numberOfLinksInNetwork < 1)
{
return 0;
}
for( int index( 0 ); index < numberOfModules ; index++)
{
numberOfLinksInModule[ index ] = numberOfLinksInModule[ index ] / 2;
}
//Calculate modularity M:
//M = sum_{s=1}^{N_{M}} [ (l_{s} / L) - (d_{s} / ( 2L ))^2 ]
//where N_{M} is the number of modules
//L is the number of links in the network
//l_{s} is the number of links between nodes in the module
//s is the module
//d_{s} is the sum of degrees of the nodes in the module
//( taken from Guimera, R. AND Amaral, L. A. N.
// Cartography of complex networks: modules and universal roles
// Journal of Statistical Mechanics: Theory and Experiment, 2005, 2005, P02001 )
for( int moduleID( 0 ); moduleID < numberOfModules; moduleID++ )
{
modularity += (((double) numberOfLinksInModule[ moduleID ]) / ((double) numberOfLinksInNetwork)) -
(
(((double) sumOfDegreesInModule[ moduleID ]) / ((double) 2 * numberOfLinksInNetwork) ) *
(((double) sumOfDegreesInModule[ moduleID ]) / ((double) 2 * numberOfLinksInNetwork) )
);
}
return modularity;
}
