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New DynamicGraph uses less RAM, Monav backport. Thanks

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Dennis Luxen 2010-09-13 14:16:07 +00:00
parent 891b068551
commit effee46011
1 changed files with 186 additions and 186 deletions
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372
DataStructures/DynamicGraph.h
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@ -16,214 +16,214 @@ You should have received a copy of the GNU Affero General Public License
along with this program; if not, write to the Free Software along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
or see http://www.gnu.org/licenses/agpl.txt. or see http://www.gnu.org/licenses/agpl.txt.
*/ */
#ifndef DYNAMICGRAPH_H_INCLUDED #ifndef DYNAMICGRAPH_H_INCLUDED
#define DYNAMICGRAPH_H_INCLUDED #define DYNAMICGRAPH_H_INCLUDED
#include <vector> #include <vector>
#include <algorithm> #include <algorithm>
#include <limits>
#include "../typedefs.h"
// returns the smallest power of two that is at least as large as x
static unsigned log2Rounded32( unsigned x ) {
const unsigned bitPosition[32] = {
0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8,
31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9
};
//round up
--x;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
++x;
//x is now a power of 2
//each power of two is mapped to a unique 5 bit sequence with ( x * 0x077CB531U ) >> 27
return bitPosition[( x * 0x077CB531U ) >> 27];
}
/*
static unsigned log2Rounded64( unsigned long long x ) {
int upperLog = log2Rounded32( x >> 32 );
if ( upperLog > 0 )
return upperLog;
return log2Rounded32( x );
}
*/
template< typename EdgeData> template< typename EdgeData>
class DynamicGraph { class DynamicGraph {
public:
typedef NodeID NodeIterator;
typedef NodeID EdgeIterator;
class InputEdge {
public: public:
EdgeData data; typedef unsigned NodeIterator;
NodeIterator source; typedef unsigned EdgeIterator;
NodeIterator target;
bool operator<( const InputEdge& right ) const {
if ( source != right.source )
return source < right.source;
return target < right.target;
}
};
DynamicGraph( int nodes, std::vector< InputEdge > &graph ) { class InputEdge {
public:
NodeIterator source;
NodeIterator target;
EdgeData data;
bool operator<( const InputEdge& right ) const {
if ( source != right.source )
return source < right.source;
return target < right.target;
}
};
std::sort( graph.begin(), graph.end() ); DynamicGraph( int nodes, const std::vector< InputEdge > &graph )
_numNodes = nodes;
_numEdges = ( EdgeIterator ) graph.size();
_nodes.resize( _numNodes );
EdgeIterator edge = 0;
EdgeIterator position = 0;
for ( NodeIterator node = 0; node < _numNodes; ++node ) {
EdgeIterator lastEdge = edge;
while ( edge < _numEdges && graph[edge].source == node ) {
++edge;
}
_nodes[node].firstEdge = position;
_nodes[node].edges = edge - lastEdge;
_nodes[node].size = 1 << log2Rounded32( edge - lastEdge );
position += _nodes[node].size;
}
_edges.resize( position );
edge = 0;
for ( NodeIterator node = 0; node < _numNodes; ++node ) {
for ( EdgeIterator i = _nodes[node].firstEdge, e = _nodes[node].firstEdge + _nodes[node].edges; i != e; ++i ) {
_edges[i].target = graph[edge].target;
_edges[i].data = graph[edge].data;
assert(_edges[i].data.distance > 0);
edge++;
}
}
}
unsigned GetNumberOfNodes() const {
return _numNodes;
}
unsigned GetNumberOfEdges() const {
return _numEdges;
}
unsigned GetOutDegree( const NodeIterator &n ) const {
return _nodes[n].edges;
}
NodeIterator GetTarget( const EdgeIterator &e ) const {
return NodeIterator( _edges[e].target );
}
EdgeData &GetEdgeData( const EdgeIterator &e ) {
return _edges[e].data;
}
const EdgeData &GetEdgeData( const EdgeIterator &e ) const {
return _edges[e].data;
}
EdgeIterator BeginEdges( const NodeIterator &n ) const {
//assert( EndEdges( n ) - EdgeIterator( _nodes[n].firstEdge ) <= 100 );
return EdgeIterator( _nodes[n].firstEdge );
}
EdgeIterator EndEdges( const NodeIterator &n ) const {
return EdgeIterator( _nodes[n].firstEdge + _nodes[n].edges );
}
//adds an edge. Invalidates edge iterators for the source node
EdgeIterator InsertEdge( const NodeIterator &from, const NodeIterator &to, const EdgeData &data ) {
_StrNode &node = _nodes[from];
if ( node.edges + 1 >= node.size ) {
node.size *= 2;
EdgeIterator newFirstEdge = ( EdgeIterator ) _edges.size();
_edges.resize( _edges.size() + node.size );
for ( unsigned i = 0; i < node.edges; ++i ) {
_edges[newFirstEdge + i ] = _edges[node.firstEdge + i];
}
node.firstEdge = newFirstEdge;
}
_StrEdge &edge = _edges[node.firstEdge + node.edges];
edge.target = to;
edge.data = data;
_numEdges++;
node.edges++;
return EdgeIterator( node.firstEdge + node.edges );
}
//removes an edge. Invalidates edge iterators for the source node
void DeleteEdge( const NodeIterator source, const EdgeIterator &e ) {
_StrNode &node = _nodes[source];
--_numEdges;
--node.edges;
const unsigned last = node.firstEdge + node.edges;
//swap with last edge
_edges[e] = _edges[last];
}
//removes all edges (source,target)
int DeleteEdgesTo( const NodeIterator source, const NodeIterator target ) {
int deleted = 0;
for ( EdgeIterator i = BeginEdges( source ), iend = EndEdges( source ); i < iend - deleted; ++i ) {
if ( _edges[i].target == target ) {
do {
deleted++;
_edges[i] = _edges[iend - deleted];
} while ( i < iend - deleted && _edges[i].target == target );
}
}
#pragma omp atomic
_numEdges -= deleted;
_nodes[source].edges -= deleted;
return deleted;
}
//searches for a specific edge
EdgeIterator FindEdge( const NodeIterator &from, const NodeIterator &to ) const {
EdgeIterator smallestEdge = SPECIAL_EDGEID;
EdgeWeight smallestWeight = UINT_MAX;
for ( EdgeIterator edge = BeginEdges( from ); edge < EndEdges(from); edge++ )
{ {
const NodeID target = GetTarget(edge); m_numNodes = nodes;
const EdgeWeight weight = GetEdgeData(edge).distance; m_numEdges = ( EdgeIterator ) graph.size();
{ m_nodes.reserve( m_numNodes );
if(target == to && weight < smallestWeight) m_nodes.resize( m_numNodes );
{ EdgeIterator edge = 0;
smallestEdge = edge; smallestWeight = weight; EdgeIterator position = 0;
for ( NodeIterator node = 0; node < m_numNodes; ++node ) {
EdgeIterator lastEdge = edge;
while ( edge < m_numEdges && graph[edge].source == node ) {
++edge;
}
m_nodes[node].firstEdge = position;
m_nodes[node].edges = edge - lastEdge;
position += m_nodes[node].edges;
}
m_edges.reserve( position * 1.2 );
m_edges.resize( position );
edge = 0;
for ( NodeIterator node = 0; node < m_numNodes; ++node ) {
for ( EdgeIterator i = m_nodes[node].firstEdge, e = m_nodes[node].firstEdge + m_nodes[node].edges; i != e; ++i ) {
m_edges[i].target = graph[edge].target;
m_edges[i].data = graph[edge].data;
edge++;
} }
} }
} }
return smallestEdge;
}
~DynamicGraph()
{
}
private: unsigned GetNumberOfNodes() const
{
return m_numNodes;
}
struct _StrNode { unsigned GetNumberOfEdges() const
//index of the first edge {
EdgeIterator firstEdge; return m_numEdges;
//amount of edges }
unsigned edges;
unsigned size;
};
struct _StrEdge { unsigned GetOutDegree( const NodeIterator &n ) const
NodeID target; {
EdgeData data; return m_nodes[n].edges;
}; }
NodeIterator _numNodes; NodeIterator GetTarget( const EdgeIterator &e ) const
EdgeIterator _numEdges; {
return NodeIterator( m_edges[e].target );
}
std::vector< _StrNode > _nodes; EdgeData &GetEdgeData( const EdgeIterator &e )
std::vector< _StrEdge > _edges; {
return m_edges[e].data;
}
const EdgeData &GetEdgeData( const EdgeIterator &e ) const
{
return m_edges[e].data;
}
EdgeIterator BeginEdges( const NodeIterator &n ) const
{
//assert( EndEdges( n ) - EdgeIterator( _nodes[n].firstEdge ) <= 100 );
return EdgeIterator( m_nodes[n].firstEdge );
}
EdgeIterator EndEdges( const NodeIterator &n ) const
{
return EdgeIterator( m_nodes[n].firstEdge + m_nodes[n].edges );
}
//adds an edge. Invalidates edge iterators for the source node
EdgeIterator InsertEdge( const NodeIterator &from, const NodeIterator &to, const EdgeData &data )
{
Node &node = m_nodes[from];
EdgeIterator newFirstEdge = node.edges + node.firstEdge;
if ( newFirstEdge >= m_edges.size() || !isDummy( newFirstEdge ) ) {
if ( node.firstEdge != 0 && isDummy( node.firstEdge - 1 ) ) {
node.firstEdge--;
m_edges[node.firstEdge] = m_edges[node.firstEdge + node.edges];
} else {
EdgeIterator newFirstEdge = ( EdgeIterator ) m_edges.size();
unsigned newSize = node.edges * 1.2 + 2;
EdgeIterator requiredCapacity = newSize + m_edges.size();
EdgeIterator oldCapacity = m_edges.capacity();
if ( requiredCapacity >= oldCapacity ) {
m_edges.reserve( requiredCapacity * 1.1 );
}
m_edges.resize( m_edges.size() + newSize );
for ( EdgeIterator i = 0; i < node.edges; ++i ) {
m_edges[newFirstEdge + i ] = m_edges[node.firstEdge + i];
makeDummy( node.firstEdge + i );
}
for ( EdgeIterator i = node.edges + 1; i < newSize; i++ )
makeDummy( newFirstEdge + i );
node.firstEdge = newFirstEdge;
}
}
Edge &edge = m_edges[node.firstEdge + node.edges];
edge.target = to;
edge.data = data;
m_numEdges++;
node.edges++;
return EdgeIterator( node.firstEdge + node.edges );
}
//removes an edge. Invalidates edge iterators for the source node
void DeleteEdge( const NodeIterator source, const EdgeIterator &e ) {
Node &node = m_nodes[source];
--m_numEdges;
--node.edges;
const unsigned last = node.firstEdge + node.edges;
//swap with last edge
m_edges[e] = m_edges[last];
makeDummy( last );
}
//removes all edges (source,target)
int DeleteEdgesTo( const NodeIterator source, const NodeIterator target )
{
int deleted = 0;
for ( EdgeIterator i = BeginEdges( source ), iend = EndEdges( source ); i < iend - deleted; ++i ) {
if ( m_edges[i].target == target ) {
do {
deleted++;
m_edges[i] = m_edges[iend - deleted];
makeDummy( iend - deleted );
} while ( i < iend - deleted && m_edges[i].target == target );
}
}
#pragma omp atomic
m_numEdges -= deleted;
m_nodes[source].edges -= deleted;
return deleted;
}
//searches for a specific edge
EdgeIterator FindEdge( const NodeIterator &from, const NodeIterator &to ) const
{
for ( EdgeIterator i = BeginEdges( from ), iend = EndEdges( from ); i != iend; ++i ) {
if ( m_edges[i].target == to ) {
return i;
}
}
return EndEdges( from );
}
protected:
bool isDummy( EdgeIterator edge ) const
{
return m_edges[edge].target == std::numeric_limits< NodeIterator >::max();
}
void makeDummy( EdgeIterator edge )
{
m_edges[edge].target = std::numeric_limits< NodeIterator >::max();
}
struct Node {
//index of the first edge
EdgeIterator firstEdge;
//amount of edges
unsigned edges;
};
struct Edge {
NodeIterator target;
EdgeData data;
};
NodeIterator m_numNodes;
EdgeIterator m_numEdges;
std::vector< Node > m_nodes;
std::vector< Edge > m_edges;
}; };
#endif // DYNAMICGRAPH_H_INCLUDED #endif // DYNAMICGRAPH_H_INCLUDED