msi.gaml.operators.Graphs.java Source code

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/*******************************************************************************************************
 *
 * msi.gaml.operators.Graphs.java, in plugin msi.gama.core, is part of the source code of the GAMA modeling and
 * simulation platform (v. 1.8)
 * 
 * (c) 2007-2018 UMI 209 UMMISCO IRD/SU & Partners
 *
 * Visit https://github.com/gama-platform/gama for license information and contacts.
 * 
 ********************************************************************************************************/
package msi.gaml.operators;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.stream.Collectors;

import org.apache.commons.lang.ArrayUtils;
import org.jgrapht.DirectedGraph;
import org.jgrapht.alg.BronKerboschCliqueFinder;
import org.jgrapht.alg.ConnectivityInspector;
import org.jgrapht.alg.flow.EdmondsKarpMFImpl;
import org.jgrapht.alg.interfaces.MaximumFlowAlgorithm.MaximumFlow;

import msi.gama.common.geometry.GeometryUtils;
import msi.gama.common.interfaces.IKeyword;
import msi.gama.metamodel.agent.IAgent;
import msi.gama.metamodel.shape.GamaPoint;
import msi.gama.metamodel.shape.ILocation;
import msi.gama.metamodel.shape.IShape;
import msi.gama.metamodel.topology.filter.In;
import msi.gama.metamodel.topology.graph.GamaSpatialGraph;
import msi.gama.metamodel.topology.graph.GamaSpatialGraph.VertexRelationship;
import msi.gama.metamodel.topology.grid.GamaSpatialMatrix.GridPopulation.GamlGridAgent;
import msi.gama.metamodel.topology.grid.GridTopology;
import msi.gama.precompiler.GamlAnnotations.doc;
import msi.gama.precompiler.GamlAnnotations.example;
import msi.gama.precompiler.GamlAnnotations.operator;
import msi.gama.precompiler.GamlAnnotations.usage;
import msi.gama.precompiler.IConcept;
import msi.gama.precompiler.IOperatorCategory;
import msi.gama.precompiler.ITypeProvider;
import msi.gama.runtime.IScope;
import msi.gama.runtime.exceptions.GamaRuntimeException;
import msi.gama.util.GamaList;
import msi.gama.util.GamaListFactory;
import msi.gama.util.GamaMap;
import msi.gama.util.GamaMapFactory;
import msi.gama.util.GamaPair;
import msi.gama.util.IContainer;
import msi.gama.util.IList;
import msi.gama.util.file.GamaFile;
import msi.gama.util.graph.GamaGraph;
import msi.gama.util.graph.GraphAlgorithmsHandmade;
import msi.gama.util.graph.GraphFromAgentContainerSynchronizer;
import msi.gama.util.graph.IGraph;
import msi.gama.util.graph.layout.AvailableGraphLayouts;
import msi.gama.util.graph.loader.GraphLoader;
import msi.gama.util.matrix.GamaFloatMatrix;
import msi.gama.util.matrix.GamaIntMatrix;
import msi.gama.util.matrix.GamaMatrix;
import msi.gama.util.path.GamaSpatialPath;
import msi.gama.util.path.IPath;
import msi.gaml.species.ISpecies;
import msi.gaml.types.GamaGraphType;
import msi.gaml.types.GamaPathType;
import msi.gaml.types.IType;
import msi.gaml.types.Types;

/**
 * Written by drogoul Modified on 13 avr. 2011
 *
 * @todo Description
 *
 */
@SuppressWarnings({ "unchecked", "rawtypes" })
public class Graphs {

    private static class IntersectionRelation implements VertexRelationship<IShape> {

        double tolerance;

        IntersectionRelation(final double t) {
            tolerance = t;
        }

        @Override
        public boolean related(final IScope scope, final IShape p1, final IShape p2) {
            return Spatial.Properties.intersects(
                    Spatial.Transformations.enlarged_by(scope, p1.getGeometry(), tolerance),
                    Spatial.Transformations.enlarged_by(scope, p2.getGeometry(), tolerance));
        }

        @Override
        public boolean equivalent(final IScope scope, final IShape p1, final IShape p2) {
            return p1 == null ? p2 == null : p1.getGeometry().equals(p2.getGeometry());
        }
    };

    private static class GridNeighborsRelation implements VertexRelationship<IShape> {

        GridNeighborsRelation() {
        }

        @Override
        public boolean related(final IScope scope, final IShape p1, final IShape p2) {
            if (!(p1 instanceof GamlGridAgent)) {
                return false;
            }
            final GridTopology topo = (GridTopology) ((GamlGridAgent) p1).getTopology();
            // ITopology topo = (((IAgent)p1).getScope().getTopology());
            return topo.getNeighborsOf(scope, p1, 1.0, In.list(scope, ((IAgent) p2).getSpecies())).contains(p2);
        }

        @Override
        public boolean equivalent(final IScope scope, final IShape p1, final IShape p2) {
            return p1 == p2;
        }
    };

    // private static class IntersectionRelationLine implements
    // VertexRelationship<IShape> {
    //
    // IntersectionRelationLine() {}
    //
    // @Override
    // public boolean related(final IScope scope, final IShape p1, final IShape
    // p2) {
    // return p1.getInnerGeometry().relate(p2.getInnerGeometry(), "****1****");
    // }
    //
    // @Override
    // public boolean equivalent(final IScope scope, final IShape p1, final
    // IShape p2) {
    // return p1 == null ? p2 == null :
    // p1.getGeometry().equals(p2.getGeometry());
    // }
    //
    // };

    private static class IntersectionRelationLineTriangle implements VertexRelationship<IShape> {

        IntersectionRelationLineTriangle() {
        }

        @Override
        public boolean related(final IScope scope, final IShape p1, final IShape p2) {
            final Set<ILocation> cp = new HashSet<>();
            final GamaPoint[] lp1 = GeometryUtils.getPointsOf(p1);
            for (final GamaPoint pt : GeometryUtils.getPointsOf(p2)) {
                if (ArrayUtils.contains(lp1, pt)) {
                    cp.add(pt);
                }
            }

            return cp.size() == 2;
        }

        @Override
        public boolean equivalent(final IScope scope, final IShape p1, final IShape p2) {
            return p1 == null ? p2 == null : p1.getGeometry().equals(p2.getGeometry());
        }

    };

    private static class DistanceRelation implements VertexRelationship<IShape> {

        double distance;

        DistanceRelation(final double d) {
            distance = d;
        }

        /**
         * @throws GamaRuntimeException
         * @see msi.gama.util.graph.GamaSpatialGraph.VertexRelationship#related(msi.gama.interfaces.IScope,
         *      msi.gama.interfaces.IGeometry, msi.gama.interfaces.IGeometry)
         */
        @Override
        public boolean related(final IScope scope, final IShape g1, final IShape g2) {
            return Spatial.Relations.distance_to(scope, g1.getGeometry(), g2.getGeometry()) <= distance;
        }

        /**
         * @throws GamaRuntimeException
         * @see msi.gama.util.graph.GamaSpatialGraph.VertexRelationship#equivalent(msi.gama.interfaces.IGeometry,
         *      msi.gama.interfaces.IGeometry)
         */
        @Override
        public boolean equivalent(final IScope scope, final IShape p1, final IShape p2) {
            return p1 == null ? p2 == null : p1.getGeometry().equals(p2.getGeometry());
        }

    }

    @operator(value = "agent_from_geometry", type = IType.AGENT, category = { IOperatorCategory.GRAPH,
            IOperatorCategory.PATH }, concept = { IConcept.GRAPH, IConcept.GEOMETRY })
    @doc(value = "returns the agent corresponding to given geometry (right-hand operand) in the given path (left-hand operand).", usages = @usage("if the left-hand operand is nil, returns nil"), examples = {
            @example(value = "geometry line <- one_of(path_followed.segments);", isExecutable = false),
            @example(value = "road ag <- road(path_followed agent_from_geometry line);", isExecutable = false) }, see = "path")
    public static IAgent getAgentFromGeom(final IPath path, final IShape geom) {
        if (path == null) {
            return null;
        }
        return (IAgent) path.getRealObject(geom);
    }

    /*
     * TO DO : CHECK THE VALIDITY OF THESE OPERATORS FOR ALL KINDS OF PATH
     *
     * @operator(value = "vertices") public static GamaList nodesOfPath(final GamaPath path) { if ( path == null ) {
     * return new GamaList(); } return path.getVertexList(); }
     *
     * @operator(value = "edges") public static GamaList edgesOfPath(final GamaPath path) { if ( path == null ) { return
     * new GamaList(); } return path.getEdgeList(); }
     */

    @operator(value = "contains_vertex", type = IType.BOOL, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH, IConcept.NODE })
    @doc(value = "returns true if the graph(left-hand operand) contains the given vertex (righ-hand operand), false otherwise", usages = @usage("if the left-hand operand is nil, returns false"), examples = {
            @example("graph graphFromMap<-  as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);"),
            @example(value = "graphFromMap contains_vertex {1,5}", equals = "true") }, see = { "contains_edge" })
    public static Boolean containsVertex(final IScope scope, final GamaGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the contains_vertex operator, the graph should not be null!",
                    scope);
        }
        return graph.containsVertex(vertex);
    }

    @operator(value = "contains_edge", type = IType.BOOL, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH, IConcept.EDGE })
    @doc(value = "returns true if the graph(left-hand operand) contains the given edge (righ-hand operand), false otherwise", masterDoc = true, usages = @usage("if the left-hand operand is nil, returns false"), examples = {
            @example("graph graphFromMap <-  as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);"),
            @example(value = "graphFromMap contains_edge link({1,5},{12,45})", equals = "true") }, see = {
                    "contains_vertex" })
    public static Boolean containsEdge(final IScope scope, final IGraph graph, final Object edge) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the contains_edge operator, the graph should not be null!", scope);
        }
        return graph.containsEdge(edge);
    }

    @operator(value = "contains_edge", type = IType.BOOL, category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "returns true if the graph(left-hand operand) contains the given edge (righ-hand operand), false otherwise", usages = @usage(value = "if the right-hand operand is a pair, returns true if it exists an edge between the two elements of the pair in the graph", examples = {
            // @example(value="graph graphEpidemio <- generate_barabasi_albert(
            // [\"edges_species\"::edge,\"vertices_specy\"::node,\"size\"::3,\"m\"::5]
            // );",isExecutable=false),
            @example(value = "graphEpidemio contains_edge (node(0)::node(3))", equals = "true", isExecutable = false) }))
    public static Boolean containsEdge(final IScope scope, final IGraph graph, final GamaPair edge) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the contains_edge operator, the graph should not be null!", scope);
        }
        return graph.containsEdge(edge.first(), edge.last());
    }

    @operator(value = "source_of", type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.EDGE, IConcept.NODE })
    @doc(value = "returns the source of the edge (right-hand operand) contained in the graph given in left-hand operand.", usages = @usage("if the lef-hand operand (the graph) is nil, throws an Exception"), examples = {
            @example(value = "graph graphEpidemio <- generate_barabasi_albert( [\"edges_species\"::edge,\"vertices_specy\"::node,\"size\"::3,\"m\"::5] );", isExecutable = false),
            @example(value = "graphEpidemio source_of(edge(3))", equals = "node1", isExecutable = false),
            @example(value = "graph graphFromMap <-  as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);"),
            @example(value = "graphFromMap source_of(link({1,5},{12,45}))", returnType = IKeyword.POINT, equals = "{1,5}") }, see = {
                    "target_of" })
    public static Object sourceOf(final IScope scope, final IGraph graph, final Object edge) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the source_of operator, the graph should not be null!", scope);
        }
        if (graph.containsEdge(edge)) {
            return graph.getEdgeSource(edge);
        }
        return null;
    }

    @operator(value = "target_of", type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.EDGE, IConcept.NODE })
    @doc(value = "returns the target of the edge (right-hand operand) contained in the graph given in left-hand operand.", usages = @usage("if the lef-hand operand (the graph) is nil, returns nil"), examples = {
            @example(value = "graph graphEpidemio <- generate_barabasi_albert( [\"edges_species\"::edge,\"vertices_specy\"::node,\"size\"::3,\"m\"::5] );", isExecutable = false),
            @example(value = "graphEpidemio source_of(edge(3))", equals = "node1", isExecutable = false),
            @example("graph graphFromMap <-  as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);"),
            @example(value = "graphFromMap target_of(link({1,5},{12,45}))", equals = "{12,45}") }, see = "source_of")
    public static Object targetOf(final IScope scope, final IGraph graph, final Object edge) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the target_of operator, the graph should not be null!", scope);
        }
        if (graph.containsEdge(edge)) {
            return graph.getEdgeTarget(edge);
        }
        return null;
    }

    @operator(value = "weight_of", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH,
            IConcept.GRAPH_WEIGHT })
    @doc(value = "returns the weight of the given edge (right-hand operand) contained in the graph given in right-hand operand.", comment = "In a localized graph, an edge has a weight by default (the distance between both vertices).", usages = {
            @usage("if the left-operand (the graph) is nil, returns nil"),
            @usage("if the right-hand operand is not an edge of the given graph, weight_of checks whether it is a node of the graph and tries to return its weight"),
            @usage("if the right-hand operand is neither a node, nor an edge, returns 1.") }, examples = {
                    @example("graph graphFromMap <-  as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);"),
                    @example(value = "graphFromMap weight_of(link({1,5},{12,45}))", equals = "1.0") })
    public static Double weightOf(final IScope scope, final IGraph graph, final Object edge) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the weight_of operator, the graph should not be null!", scope);
        }
        if (graph.containsEdge(edge)) {
            return graph.getEdgeWeight(edge);
        } else if (graph.containsVertex(edge)) {
            return graph.getVertexWeight(edge);
        }
        return 1d;
    }

    @operator(value = "in_edges_of", type = IType.LIST, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.EDGE })
    @doc(value = "returns the list of the in-edges of a vertex (right-hand operand) in the graph given as left-hand operand.", examples = {
            @example(value = "graph graphFromMap <- graph([]);", isTestOnly = true),
            @example(value = "graphFromMap in_edges_of node({12,45})", equals = "[LineString]", test = false) }, see = "out_edges_of")
    public static IList inEdgesOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the in_edges_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return GamaListFactory.create(scope, graph.getGamlType().getContentType(),
                    graph.incomingEdgesOf(vertex));
        }
        return GamaListFactory.create(graph.getGamlType().getContentType());
    }

    @operator(value = "edge_between", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH, IConcept.EDGE })
    @doc(value = "returns the edge linking two nodes", examples = {
            @example(value = "graphFromMap edge_between node1::node2", equals = "edge1", isExecutable = false) }, see = {
                    "out_edges_of", "in_edges_of" })
    public static Object EdgeBetween(final IScope scope, final IGraph graph, final GamaPair verticePair) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the edge_between operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(verticePair.key) && graph.containsVertex(verticePair.value)) {
            return graph.getEdge(verticePair.key, verticePair.value);
        }
        return null;
    }

    @operator(value = "in_degree_of", type = IType.INT, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH, IConcept.NODE })
    @doc(value = "returns the in degree of a vertex (right-hand operand) in the graph given as left-hand operand.", examples = {
            @example(value = "graph graphFromMap <- graph([]);", isTestOnly = true),
            @example(value = "graphFromMap in_degree_of (node(3))", equals = "2", test = false) }, see = {
                    "out_degree_of", "degree_of" })
    public static int inDregreeOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the in_degree_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return graph.inDegreeOf(vertex);
        }
        return 0;
    }

    @operator(value = "out_edges_of", type = IType.LIST, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the list of the out-edges of a vertex (right-hand operand) in the graph given as left-hand operand.", masterDoc = true, examples = {
            @example(value = "graph graphFromMap <- graph([]);", isTestOnly = true),
            @example(value = "graphFromMap out_edges_of (node(3))", equals = "3", test = false) }, see = "in_edges_of")
    public static IList outEdgesOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the out_edges_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return GamaListFactory.create(scope, graph.getGamlType().getContentType(),
                    graph.outgoingEdgesOf(vertex));
        }
        return GamaListFactory.create(graph.getGamlType().getContentType());
    }

    @operator(value = "out_degree_of", type = IType.INT, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the out degree of a vertex (right-hand operand) in the graph given as left-hand operand.", examples = {
            @example(value = "graph graphFromMap <- graph([]);", isTestOnly = true),
            @example(value = "graphFromMap out_degree_of (node(3))", equals = "4", test = false) }, see = {
                    "in_degree_of", "degree_of" })
    public static int outDregreeOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the in_degree_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return graph.outDegreeOf(vertex);
        }
        return 0;
    }

    @operator(value = "degree_of", type = IType.INT, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH, IConcept.NODE })
    @doc(value = "returns the degree (in+out) of a vertex (right-hand operand) in the graph given as left-hand operand.", examples = {
            @example(value = "graph graphFromMap <- graph([]);", isTestOnly = true),
            @example(value = "graphFromMap degree_of (node(3))", equals = "3", test = false) }, see = {
                    "in_degree_of", "out_degree_of" })
    public static int degreeOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the in_degree_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return graph.degreeOf(vertex);
        }
        return 0;
    }

    @operator(value = "connected_components_of", type = IType.LIST, content_type = IType.LIST, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the connected components of a graph, i.e. the list of all vertices that are in the maximally connected component together with the specified vertex. ", examples = {
            @example(value = "graph my_graph <- graph([]);"),
            @example(value = "connected_components_of (my_graph)", equals = "the list of all the components as list", test = false) }, see = {
                    "alpha_index", "connectivity_index", "nb_cycles" })
    public static IList<IList> connectedComponentOf(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException
                    .error("In the connected_components_of operator, the graph should not be null!", scope);
        }

        ConnectivityInspector ci;
        // there is an error with connectivity inspector of JGrapht....
        ci = new ConnectivityInspector((DirectedGraph) graph);
        final IList<IList> results = GamaListFactory.create(Types.LIST);
        for (final Object obj : ci.connectedSets()) {
            results.add(GamaListFactory.create(scope, graph.getGamlType().getContentType(), (Set) obj));

        }
        return results;
    }

    @operator(value = "connected_components_of", type = IType.LIST, content_type = IType.LIST, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the connected components of a graph, i.e. the list of all edges (if the boolean is true) or vertices (if the boolean is false) that are in the connected components. ", examples = {
            @example(value = "graph my_graph2 <- graph([]);"),
            @example(value = "connected_components_of (my_graph2, true)", equals = "the list of all the components as list", test = false) }, see = {
                    "alpha_index", "connectivity_index", "nb_cycles" })
    public static IList<IList> connectedComponentOf(final IScope scope, final IGraph graph, final boolean edge) {
        if (graph == null) {
            throw GamaRuntimeException
                    .error("In the connected_components_of operator, the graph should not be null!", scope);
        }

        ConnectivityInspector ci;
        // there is an error with connectivity inspector of JGrapht....
        ci = new ConnectivityInspector((DirectedGraph) graph);
        final IList<IList> results = GamaListFactory.create(Types.LIST);
        for (final Object obj : ci.connectedSets()) {
            if (edge) {
                final IList edges = GamaListFactory.create(scope, graph.getGamlType().getContentType());
                for (final Object v : (Set) obj) {
                    edges.addAll(graph.edgesOf(v));
                }

                results.add(Containers.remove_duplicates(scope, edges));

            } else {
                results.add(GamaListFactory.create(scope, graph.getGamlType().getKeyType(), (Set) obj));
            }
        }
        return results;
    }

    @operator(value = "main_connected_component", type = IType.GRAPH, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the sub-graph corresponding to the main connected components of the graph", examples = {
            @example(value = "main_connected_component(my_graph)", isExecutable = false, equals = "the sub-graph corresponding to the main connected components of the graph", test = false) }, see = {
                    "connected_components_of" })
    public static IGraph ReduceToMainconnectedComponentOf(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException
                    .error("In the connected_components_of operator, the graph should not be null!", scope);
        }

        final IList<IList> cc = connectedComponentOf(scope, graph);
        final IGraph newGraph = (IGraph) graph.copy(scope);
        IList mainCC = null;
        int size = 0;
        for (final IList c : cc) {
            if (c.size() > size) {
                size = c.size();
                mainCC = c;
            }
        }
        if (mainCC != null) {
            final Set vs = graph.vertexSet();
            vs.removeAll(mainCC);
            for (final Object v : vs) {
                newGraph.removeVertex(v);
            }
        }

        return newGraph;
    }

    @operator(value = "maximal_cliques_of", type = IType.LIST, content_type = IType.LIST, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the maximal cliques of a graph using the Bron-Kerbosch clique detection algorithm: A clique is maximal if it is impossible to enlarge it by adding another vertex from the graph. Note that a maximal clique is not necessarily the biggest clique in the graph. ", examples = {
            @example(value = "graph my_graph <- graph([]);"),
            @example(value = "maximal_cliques_of (my_graph)", equals = "the list of all the maximal cliques as list", test = false) }, see = {
                    "biggest_cliques_of" })
    public static IList<IList> getMaximalCliques(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the maximal_cliques_of operator, the graph should not be null!",
                    scope);
        }
        final BronKerboschCliqueFinder cls = new BronKerboschCliqueFinder(graph);
        final IList<IList> results = GamaListFactory.create(Types.LIST);
        final Collection cliques = cls.getAllMaximalCliques();
        for (final Object obj : cliques) {
            results.add(GamaListFactory.create(scope, graph.getGamlType().getKeyType(), (Set) obj));
        }
        return results;
    }

    @operator(value = "biggest_cliques_of", type = IType.LIST, content_type = IType.LIST, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE })
    @doc(value = "returns the biggest cliques of a graph using the Bron-Kerbosch clique detection algorithm", examples = {
            @example(value = "graph my_graph <- graph([]);"),
            @example(value = "biggest_cliques_of (my_graph)", equals = "the list of the biggest cliques as list", test = false) }, see = {
                    "maximal_cliques_of" })
    public static IList<IList> getBiggestCliques(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the biggest_cliques_of operator, the graph should not be null!",
                    scope);
        }
        final BronKerboschCliqueFinder cls = new BronKerboschCliqueFinder(graph);

        final IList<IList> results = GamaListFactory.create(Types.LIST);
        final Collection cliques = cls.getBiggestMaximalCliques();
        for (final Object obj : cliques) {
            results.add(GamaListFactory.create(scope, graph.getGamlType().getKeyType(), (Set) obj));
        }
        return results;
    }

    @operator(value = "nb_cycles", type = IType.INT, category = { IOperatorCategory.GRAPH }, concept = {
            IConcept.GRAPH })
    @doc(value = "returns the maximum number of independent cycles in a graph. This number (u) is estimated through the number of nodes (v), links (e) and of sub-graphs (p): u = e - v + p.", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "nb_cycles(graphEpidemio)", equals = "the number of cycles in the graph", test = false) }, see = {
                    "alpha_index", "beta_index", "gamma_index", "connectivity_index" })
    public static int nbCycles(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the nb_cycles operator, the graph should not be null!", scope);
        }
        final int S = graph.vertexSet().size();
        final int C = connectedComponentOf(scope, graph).size();
        final int L = graph.edgeSet().size();
        return L - S + C;
    }

    @operator(value = "alpha_index", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns the alpha index of the graph (measure of connectivity which evaluates the number of cycles in a graph in comparison with the maximum number of cycles. The higher the alpha index, the more a network is connected: alpha = nb_cycles / (2`*`S-5) - planar graph)", examples = {
            @example(value = "graph graphEpidemio <- graph([]);", isTestOnly = true),
            @example(value = "alpha_index(graphEpidemio)", equals = "the alpha index of the graph", test = false) }, see = {
                    "beta_index", "gamma_index", "nb_cycles", "connectivity_index" })
    public static double alphaIndex(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the alpha_index operator, the graph should not be null!", scope);
        }
        final int S = graph.vertexSet().size();
        return nbCycles(scope, graph) / (2.0 * S - 5);
    }

    @operator(value = "beta_index", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns the beta index of the graph (Measures the level of connectivity in a graph and is expressed by the relationship between the number of links (e) over the number of nodes (v) : beta = e/v.", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "beta_index(graphEpidemio)", equals = "the beta index of the graph", test = false) }, see = {
                    "alpha_index", "gamma_index", "nb_cycles", "connectivity_index" })
    public static double betaIndex(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the beta_index operator, the graph should not be null!", scope);
        }
        return (graph.edgeSet().size() + 0.0) / graph.vertexSet().size();
    }

    @operator(value = "gamma_index", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns the gamma index of the graph (A measure of connectivity that considers the relationship between the number of observed links and the number of possible links: gamma = e/(3 `*` (v - 2)) - for planar graph.", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "gamma_index(graphEpidemio)", equals = "the gamma index of the graph", test = false) }, see = {
                    "alpha_index", "beta_index", "nb_cycles", "connectivity_index" })
    public static double gammaIndex(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the gamma_index operator, the graph should not be null!", scope);
        }
        return graph.edgeSet().size() / (2.0 * graph.vertexSet().size() - 5);
    }

    @operator(value = "connectivity_index", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns a simple connectivity index. This number is estimated through the number of nodes (v) and of sub-graphs (p) : IC = (v - p) /(v - 1).", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "connectivity_index(graphEpidemio)", equals = "the connectivity index of the graph", test = false) }, see = {
                    "alpha_index", "beta_index", "gamma_index", "nb_cycles" })
    public static double connectivityIndex(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the connectivity_index operator, the graph should not be null!",
                    scope);
        }
        final int S = graph.vertexSet().size();
        final int C = connectedComponentOf(scope, graph).size();
        return (S - C) / (S - 1.0);
    }

    @operator(value = "betweenness_centrality", type = IType.MAP, content_type = IType.INT, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns a map containing for each vertex (key), its betweenness centrality (value): number of shortest paths passing through each vertex ", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "betweenness_centrality(graphEpidemio)", equals = "the betweenness centrality index of the graph", test = false) }, see = {})
    public static GamaMap betweennessCentrality(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException
                    .error("In the betweenness_centrality operator, the graph should not be null!", scope);
        }
        // DEBUG.OUT("result.getRaw() : " + result.getRaw());

        final GamaMap mapResult = GamaMapFactory.create(graph.getGamlType().getKeyType(), Types.INT);
        final GamaList vertices = (GamaList) Cast.asList(scope, graph.vertexSet());
        for (final Object v : vertices) {
            mapResult.put(v, 0);
        }
        final boolean directed = graph.isDirected();
        for (int i = 0; i < vertices.size(); i++) {
            for (int j = directed ? 0 : i + 1; j < vertices.size(); j++) {
                final Object v1 = vertices.get(i);
                final Object v2 = vertices.get(j);
                if (v1 == v2) {
                    continue;
                }
                final List edges = graph.computeBestRouteBetween(scope, v1, v2);
                if (edges == null) {
                    continue;
                }
                Object vc = v1;
                for (final Object edge : edges) {
                    Object node = graph.getEdgeTarget(edge);
                    if (node == vc) {
                        node = graph.getEdgeSource(edge);
                    }
                    if (node != v2 && node != v1) {
                        mapResult.put(node, (Integer) mapResult.get(node) + 1);
                    }
                    vc = node;
                }
            }
        }
        return mapResult;
    }

    @operator(value = "edge_betweenness", type = IType.MAP, content_type = IType.INT, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "returns a map containing for each edge (key), its betweenness centrality (value): number of shortest paths passing through each edge ", examples = {
            @example(value = "graph graphEpidemio <- graph([]);"),
            @example(value = "edge_betweenness(graphEpidemio)", equals = "the edge betweenness index of the graph", test = false) }, see = {})
    public static GamaMap edgeBetweenness(final IScope scope, final IGraph graph) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the edge_betweenness operator, the graph should not be null!",
                    scope);
        }
        // DEBUG.OUT("result.getRaw() : " + result.getRaw());

        final GamaMap mapResult = GamaMapFactory.create(graph.getGamlType().getKeyType(), Types.INT);
        for (final Object v : graph.edgeSet()) {
            mapResult.put(v, 0);
        }
        final GamaList vertices = (GamaList) Cast.asList(scope, graph.vertexSet());
        final boolean directed = graph.isDirected();
        for (int i = 0; i < vertices.size(); i++) {
            for (int j = directed ? 0 : i + 1; j < vertices.size(); j++) {
                final Object v1 = vertices.get(i);
                final Object v2 = vertices.get(j);
                if (v1 == v2) {
                    continue;
                }
                final List edges = graph.computeBestRouteBetween(scope, v1, v2);
                if (edges == null) {
                    continue;
                }
                for (final Object edge : edges) {
                    mapResult.put(edge, (Integer) mapResult.get(edge) + 1);
                }
            }
        }
        return mapResult;
    }

    @operator(value = { "neighbors_of" }, type = IType.LIST, content_type = ITypeProvider.KEY_TYPE_AT_INDEX
            + 1, category = {
                    IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.NEIGHBORS })
    @doc(value = "returns the list of neighbors of the given vertex (right-hand operand) in the given graph (left-hand operand)", examples = {
            @example(value = "graphEpidemio neighbors_of (node(3))", equals = "[node0,node2]", isExecutable = false),
            @example(value = "graphFromMap neighbors_of node({12,45})", equals = "[{1.0,5.0},{34.0,56.0}]", isExecutable = false) }, see = {
                    "predecessors_of", "successors_of" })
    public static IList neighborsOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph == null) {
            throw GamaRuntimeException.error("In the neighbors_of operator, the graph should not be null!", scope);
        }
        if (graph.containsVertex(vertex)) {
            return GamaListFactory.create(scope, graph.getGamlType().getKeyType(),
                    org.jgrapht.Graphs.neighborListOf(graph, vertex));
        }
        return GamaListFactory.create(graph.getGamlType().getKeyType());
    }

    @operator(value = "predecessors_of", type = IType.LIST, content_type = ITypeProvider.KEY_TYPE_AT_INDEX
            + 1, category = {
                    IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.NEIGHBORS })
    @doc(value = "returns the list of predecessors (i.e. sources of in edges) of the given vertex (right-hand operand) in the given graph (left-hand operand)", examples = {
            @example(value = "graph graphEpidemio <- as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);", isTestOnly = true),
            @example(value = "graphEpidemio predecessors_of ({1,5})", equals = "[]", test = false),
            @example(value = "graphEpidemio predecessors_of node({34,56})", equals = "[{12;45}]", test = false) }, see = {
                    "neighbors_of", "successors_of" })
    public static IList predecessorsOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph.containsVertex(vertex)) {
            return GamaListFactory.create(scope, graph.getGamlType().getKeyType(),
                    org.jgrapht.Graphs.predecessorListOf(graph, vertex));
        }
        return GamaListFactory.create(graph.getGamlType().getKeyType());
    }

    @operator(value = "successors_of", content_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.NEIGHBORS })
    @doc(value = "returns the list of successors (i.e. targets of out edges) of the given vertex (right-hand operand) in the given graph (left-hand operand)", examples = {
            @example(value = "graph graphEpidemio <- as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);", isTestOnly = true),
            @example(value = "graphEpidemio successors_of ({1,5})", equals = "[{12,45}]"),
            @example(value = "graphEpidemio successors_of node({34,56})", equals = "[]") }, see = {
                    "predecessors_of", "neighbors_of" })
    public static IList successorsOf(final IScope scope, final IGraph graph, final Object vertex) {
        if (graph.containsVertex(vertex)) {
            return GamaListFactory.create(scope, graph.getGamlType().getKeyType(),
                    org.jgrapht.Graphs.successorListOf(graph, vertex));
        }
        return GamaListFactory.create(graph.getGamlType().getKeyType());
    }

    // @operator(value = "graph_from_edges")
    // public static IGraph fromEdges(final IScope scope, final GamaList edges)
    // {
    // return new GamaGraph(edges, true, false);
    // }

    @operator(value = "as_edge_graph", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = IType.GEOMETRY, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH,
                    IConcept.CAST, IConcept.MAP, IConcept.LIST, IConcept.EDGE })
    @doc(value = "creates a graph from the list/map of edges given as operand", masterDoc = true, usages = @usage(value = "if the operand is a list, the graph will be built with elements of the list as edges", examples = {
            @example(value = "as_edge_graph([line([{1,5},{12,45}]),line([{12,45},{34,56}])])", equals = "a graph with two edges and three vertices", test = false) }), see = {
                    "as_intersection_graph", "as_distance_graph" })
    public static IGraph spatialFromEdges(final IScope scope, final IContainer edges) {

        final IGraph createdGraph = new GamaSpatialGraph(edges, true, false, null, null, scope, Types.GEOMETRY,
                edges.getGamlType().getContentType());
        if (Types.AGENT.equals(edges.getGamlType().getContentType())) {
            GraphFromAgentContainerSynchronizer.synchronize(scope, null, edges, createdGraph);
        }

        return createdGraph;
    }

    @operator(value = "as_edge_graph", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = IType.GEOMETRY, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH,
                    IConcept.CAST, IConcept.MAP, IConcept.LIST, IConcept.EDGE })
    @doc(usages = @usage(value = "if the operand is a list and a tolerance (max distance in meters to consider that 2 points are the same node) is given, "
            + "the graph will be built with elements of the list as edges and two edges will be connected by a node if the distance between their "
            + "extremity (first or last points) are at distance lower or equal to the tolerance", examples = {
                    @example(value = "as_edge_graph([line([{1,5},{12,45}]),line([{13,45},{34,56}])],1)", equals = "a graph with two edges and three vertices", test = false) }), see = {
                            "as_intersection_graph", "as_distance_graph" })
    public static IGraph spatialFromEdges(final IScope scope, final IContainer edges, final Double tolerance) {

        final GamaSpatialGraph createdGraph = new GamaSpatialGraph(edges, true, false, null, null, scope,
                Types.GEOMETRY, edges.getGamlType().getContentType(), tolerance);

        if (Types.AGENT.equals(edges.getGamlType().getContentType())) {
            GraphFromAgentContainerSynchronizer.synchronize(scope, null, edges, createdGraph);
        }

        return createdGraph;
    }

    // @operator(value = "graph_from_edges")
    // public static IGraph fromEdges(final IScope scope, final GamaMap edges) {
    // Edges are represented by pairs of vertex::vertex
    // return GamaGraphType.from(edges, false);
    // }

    @operator(value = "as_edge_graph", index_type = ITypeProvider.CONTENT_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = @usage(value = "if the operand is a map, the graph will be built by creating edges from pairs of the map", examples = @example(value = "as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}])", equals = "a graph with these three vertices and two edges", test = false)))
    public static IGraph spatialFromEdges(final IScope scope, final GamaMap edges) {
        // Edges are represented by pairs of vertex::vertex

        return GamaGraphType.from(scope, edges, true);
    }

    // @operator(value = "graph_from_vertices")
    // public static IGraph fromVertices(final IScope scope, final GamaList
    // vertices) {
    // return new GamaGraph(vertices, false, false);
    // }

    @operator(value = "as_intersection_graph", content_type = IType.GEOMETRY, index_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.CAST })
    @doc(value = "creates a graph from a list of vertices (left-hand operand). An edge is created between each pair of vertices with an intersection (with a given tolerance).", comment = "as_intersection_graph is more efficient for a list of geometries (but less accurate) than as_distance_graph.", examples = @example(value = "list(ant) as_intersection_graph 0.5", isExecutable = false), see = {
            "as_distance_graph", "as_edge_graph" })
    public static IGraph spatialFromVertices(final IScope scope, final IContainer vertices,
            final Double tolerance) {
        final IGraph createdGraph = new GamaSpatialGraph(vertices, false, false,
                new IntersectionRelation(tolerance), null, scope, vertices.getGamlType().getContentType(),
                Types.GEOMETRY);
        if (Types.AGENT.equals(vertices.getGamlType().getContentType())) {
            GraphFromAgentContainerSynchronizer.synchronize(scope, vertices, null, createdGraph);
        }
        return createdGraph;
    }

    public static IGraph spatialLineIntersection(final IScope scope, final IContainer vertices) {
        return new GamaSpatialGraph(vertices, false, false, new IntersectionRelationLineTriangle(), null, scope,
                vertices.getGamlType().getContentType(), Types.GEOMETRY);
    }

    @operator(value = "as_distance_graph", content_type = IType.GEOMETRY, index_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE, IConcept.EDGE,
                    IConcept.CAST })
    @doc(value = "creates a graph from a list of vertices (left-hand operand). An edge is created between each pair of vertices close enough (less than a distance, right-hand operand).", masterDoc = true, comment = "as_distance_graph is more efficient for a list of points than as_intersection_graph.", examples = @example(value = "list(ant) as_distance_graph 3.0", isExecutable = false), see = {
            "as_intersection_graph", "as_edge_graph" })
    public static IGraph spatialDistanceGraph(final IScope scope, final IContainer vertices,
            final Double distance) {
        final IGraph createdGraph = new GamaSpatialGraph(vertices, false, false, new DistanceRelation(distance),
                null, scope, vertices.getGamlType().getContentType(), Types.GEOMETRY);
        if (Types.AGENT.equals(vertices.getGamlType().getContentType())) {
            GraphFromAgentContainerSynchronizer.synchronize(scope, vertices, null, createdGraph);
        }
        return createdGraph;
    }

    @operator(value = "grid_cells_to_graph", content_type = IType.GEOMETRY, index_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.GRID, IConcept.CAST,
                    IConcept.NEIGHBORS })
    @doc(value = "creates a graph from a list of cells (operand). An edge is created between neighbors.", masterDoc = true, comment = "", examples = @example(value = "my_cell_graph<-grid_cells_to_graph(cells_list)", isExecutable = false), see = {})
    public static IGraph gridCellsToGraph(final IScope scope, final IContainer vertices) {
        final IGraph graph = new GamaSpatialGraph(vertices, false, false, new GridNeighborsRelation(), null, scope,
                vertices.getGamlType().getContentType(), Types.GEOMETRY);
        for (final Object e : graph.edgeSet()) {
            graph.setEdgeWeight(e, ((IShape) e).getPerimeter());
        }
        return graph;
    }

    @operator(value = "as_distance_graph", content_type = IType.GEOMETRY, index_type = IType.GEOMETRY, category = {
            IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "creates a graph from a list of vertices (left-hand operand). An edge is created between each pair of vertices close enough (less than a distance, right-hand operand).", see = {
            "as_intersection_graph", "as_edge_graph" })
    public static IGraph spatialDistanceGraph(final IScope scope, final IContainer vertices, final Double distance,
            final ISpecies edgeSpecies) {
        final IType edgeType = scope.getType(edgeSpecies.getName());
        final IGraph createdGraph = new GamaSpatialGraph(vertices, false, false, new DistanceRelation(distance),
                edgeSpecies, scope, vertices.getGamlType().getContentType(), edgeType);

        GraphFromAgentContainerSynchronizer.synchronize(scope, vertices, edgeSpecies, createdGraph);

        return createdGraph;
    }

    @operator(value = "as_distance_graph", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "creates a graph from a list of vertices (left-hand operand). An edge is created between each pair of vertices close enough (less than a distance, right-hand operand).", see = {
            "as_intersection_graph", "as_edge_graph" })
    public static IGraph spatialDistanceGraph(final IScope scope, final IContainer vertices, final GamaMap params) {
        final Double distance = (Double) params.get("distance");
        final ISpecies edgeSpecies = (ISpecies) params.get("species");
        final IType edgeType = edgeSpecies == null ? Types.GEOMETRY : scope.getType(edgeSpecies.getName());
        final IGraph createdGraph = new GamaSpatialGraph(vertices, false, false, new DistanceRelation(distance),
                edgeSpecies, scope, vertices.getGamlType().getContentType(), edgeType);

        if (Types.AGENT.equals(vertices.getGamlType().getContentType())) {
            GraphFromAgentContainerSynchronizer.synchronize(scope, vertices, edgeSpecies, createdGraph);
        }
        return createdGraph;
    }

    @operator(value = "spatial_graph", index_type = ITypeProvider.CONTENT_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.GEOMETRY, IConcept.POINT })
    @doc(value = "allows to create a spatial graph from a container of vertices, without trying to wire them. The container can be empty. Emits an error if the contents of the container are not geometries, points or agents", see = {
            "graph" })
    public static IGraph spatial_graph(final IScope scope, final IContainer vertices) {
        return new GamaSpatialGraph(vertices, false, false, null, null, scope,
                vertices.getGamlType().getContentType(), Types.GEOMETRY);
    }

    // @operator(value = "spatialize")
    // public static IGraph asSpatialGraph(final GamaGraph g) {
    // return GamaGraphType.asSpatialGraph(g);
    // }

    // @operator(value = "unspatialize")
    // public static IGraph asRegularGraph(final GamaGraph g) {
    // return GamaGraphType.asRegularGraph(g);
    // }

    @operator(value = "use_cache", category = { IOperatorCategory.GRAPH, IOperatorCategory.PATH }, concept = {
            IConcept.GRAPH, IConcept.SHORTEST_PATH })
    @doc(value = "if the second operand is true, the operand graph will store in a cache all the previously computed shortest path (the cache be cleared if the graph is modified).", comment = "the operator alters the operand graph, it does not create a new one.", see = {
            "path_between" })
    public static IGraph useCacheForShortestPaths(final IGraph g, final boolean useCache) {
        return GamaGraphType.useChacheForShortestPath(g, useCache);
    }

    @operator(value = "directed", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "the operand graph becomes a directed graph.", comment = "the operator alters the operand graph, it does not create a new one.", see = {
            "undirected" })
    public static IGraph asDirectedGraph(final IGraph g) {
        g.incVersion();
        return GamaGraphType.asDirectedGraph(g);
    }

    @operator(value = "undirected", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
                    IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.SHORTEST_PATH })
    @doc(value = "the operand graph becomes an undirected graph.", comment = "the operator alters the operand graph, it does not create a new one.", see = {
            "directed" })
    public static IGraph asUndirectedGraph(final IGraph g) {
        g.incVersion();
        return GamaGraphType.asUndirectedGraph(g);
    }

    @operator(value = "with_weights", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
                    IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.GRAPH_WEIGHT })
    @doc(value = "returns the graph (left-hand operand) with weight given in the map (right-hand operand).", masterDoc = true, comment = "this operand re-initializes the path finder", usages = @usage(value = "if the left-hand operand is a map, the map should contains pairs such as: vertex/edge::double", examples = @example(value = "graph_from_edges (list(ant) as_map each::one_of (list(ant))) with_weights (list(ant) as_map each::each.food)", isExecutable = false)))
    public static IGraph withWeights(final IScope scope, final IGraph graph, final GamaMap weights) {
        // a map of vertex/edge::double to provide weights
        // Example : graph_from_edges (list ant as_map each::one_of (list ant))
        // with_weights (list
        // ant as_map each::each.food)
        graph.setWeights(weights);
        graph.incVersion();
        if (graph instanceof GamaSpatialGraph) {
            ((GamaSpatialGraph) graph).reInitPathFinder();
        }
        return graph;
    }

    @operator(value = "with_weights", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = @usage("if the right-hand operand is a list, affects the n elements of the list to the n first edges. "
            + "Note that the ordering of edges may change overtime, which can create some problems..."))
    public static IGraph withWeights(final IScope scope, final IGraph graph, final IList weights) {
        // Simply a list of double... and, by default, for edges.However, the
        // ordering of edges may
        // change overtime, which can create a problem somewhere...
        final IList edges = graph.getEdges();
        final int n = edges.size();
        if (n != weights.size()) {
            return graph;
        }
        for (int i = 0; i < n; i++) {
            graph.setEdgeWeight(edges.get(i), Cast.asFloat(scope, weights.get(i)));
        }
        graph.incVersion();
        if (graph instanceof GamaSpatialGraph) {
            ((GamaSpatialGraph) graph).reInitPathFinder();
        }
        return graph;
    }

    @operator(value = "with_optimizer_type", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = {
                    IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.SHORTEST_PATH,
                            IConcept.GRAPH_WEIGHT, IConcept.OPTIMIZATION, IConcept.ALGORITHM })
    @doc(value = "changes the shortest path computation method of the given graph", comment = "the right-hand operand can be \"Djikstra\", \"Bellmann\", \"Astar\" to use the associated algorithm. "
            + "Note that these methods are dynamic: the path is computed when needed. In contrarily, if the operand is another string, "
            + "a static method will be used, i.e. all the shortest are previously computed.", examples = @example(value = "graphEpidemio <- graphEpidemio with_optimizer_type \"static\";", isExecutable = false), see = "set_verbose")
    public static IGraph setOptimizeType(final IScope scope, final IGraph graph, final String optimizerType) {
        final List<String> existingOptimizer = Arrays.asList(GamaGraph.shortestPathAlgorithm.values()).stream()
                .map(a -> a.toString()).collect(Collectors.toList());
        if (existingOptimizer.contains(optimizerType)) {
            graph.setOptimizerType(optimizerType);
        } else {
            throw GamaRuntimeException.error("The Optimizer type " + optimizerType
                    + " does not exist. Possible optimizer types: " + existingOptimizer, scope);
        }
        return graph;
    }

    @operator(value = "add_node", type = IType.GRAPH, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE })
    @doc(value = "adds a node in a graph.", examples = @example(value = "graph add_node node(0) ", equals = "the graph with node(0)", isExecutable = false), see = {
            "add_edge", "graph" })
    public static IGraph addNode(final IGraph g, final IShape node) {
        g.addVertex(node);
        return g;
    }

    @operator(value = "remove_node_from", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.NODE })
    @doc(value = "removes a node from a graph.", comment = "all the edges containing this node are also removed.", examples = @example(value = "node(0) remove_node_from graphEpidemio", equals = "the graph without node(0)", isExecutable = false))
    public static IGraph removeNodeFrom(final IShape node, final IGraph g) {
        g.removeVertex(node);

        return g;
    }

    @operator(value = "rewire_n", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.EDGE })
    @doc(value = "rewires the given count of edges.", comment = "If there are too many edges, all the edges will be rewired.", examples = {
            @example(value = "graph graphEpidemio <- as_edge_graph([{1,5}::{12,45},{12,45}::{34,56}]);", isTestOnly = true),
            @example(value = "graphEpidemio rewire_n 10", equals = "the graph with 3 edges rewired", test = false) })
    public static IGraph rewireGraph(final IScope scope, final IGraph g, final Integer count) {
        GraphAlgorithmsHandmade.rewireGraphCount(scope, g, count);
        g.incVersion();
        return g;
    }

    @operator(value = "add_edge", type = IType.GRAPH, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH, IConcept.EDGE })
    @doc(value = "add an edge between a source vertex and a target vertex (resp. the left and the right element of the pair operand)", comment = "if the edge already exists, the graph is unchanged", examples = @example(value = "graph <- graph add_edge (source::target);", isExecutable = false), see = {
            "add_node", "graph" })
    public static IGraph addEdge(final IGraph g, final GamaPair nodes) {
        g.addEdge(nodes.first(), nodes.last());
        g.incVersion();
        return g;
    }

    @operator(value = "path_between", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH, IOperatorCategory.PATH }, concept = { IConcept.GRAPH })
    @doc(value = "The shortest path between a list of two objects in a graph", masterDoc = true, examples = {
            @example(value = "path_between (my_graph, ag1, ag2)", equals = "A path between ag1 and ag2", isExecutable = false) })
    public static IPath path_between(final IScope scope, final IGraph graph, final IShape source,
            final IShape target) throws GamaRuntimeException {
        // DEBUG.OUT("Cast.asTopology(scope, graph) : " +
        // Cast.asTopology(scope, graph));
        if (graph instanceof GamaSpatialGraph) {
            return Cast.asTopology(scope, graph).pathBetween(scope, source, target);
        }
        return graph.computeShortestPathBetween(scope, source, target);
        // return graph.computeShortestPathBetween(sourTarg.key,
        // sourTarg.value);
    }

    @operator(value = "paths_between", type = IType.LIST, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH, IOperatorCategory.PATH }, concept = { IConcept.GRAPH })
    @doc(value = "The K shortest paths between a list of two objects in a graph", examples = {
            @example(value = "paths_between(my_graph, ag1:: ag2, 2)", equals = "the 2 shortest paths (ordered by length) between ag1 and ag2", isExecutable = false) })
    public static IList<GamaSpatialPath> Kpaths_between(final IScope scope, final GamaGraph graph,
            final GamaPair sourTarg, final int k) throws GamaRuntimeException {
        // DEBUG.OUT("Cast.asTopology(scope, graph) : " +
        // Cast.asTopology(scope, graph));
        return Cast.asTopology(scope, graph).KpathsBetween(scope, (IShape) sourTarg.key, (IShape) sourTarg.value,
                k);

        // return graph.computeShortestPathBetween(sourTarg.key,
        // sourTarg.value);

    }

    @operator(value = "max_flow_between", type = IType.LIST, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH, IOperatorCategory.PATH }, concept = { IConcept.GRAPH })
    @doc(value = "The max flow (map<edge,flow> in a graph between the source and the sink using Edmonds-Karp algorithm", examples = {
            @example(value = "max_flow_between(my_graph, vertice1, vertice2)", isExecutable = false) })
    public static GamaMap<Object, Double> maxFlowBetween(final IScope scope, final GamaGraph graph,
            final Object source, final Object sink) throws GamaRuntimeException {
        final EdmondsKarpMFImpl ek = new EdmondsKarpMFImpl(graph);
        final MaximumFlow<IShape> mf = ek.getMaximumFlow(source, sink);
        final GamaMap<Object, Double> result = GamaMapFactory.create();
        result.putAll(mf.getFlow());
        return result;
    }

    @operator(value = "as_path", type = IType.PATH, content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, category = { IOperatorCategory.GRAPH,
                    IOperatorCategory.PATH }, concept = { IConcept.GRAPH, IConcept.CAST })
    @doc(value = "create a graph path from the list of shape", examples = {
            @example(value = "[road1,road2,road3] as_path my_graph", equals = "a path road1->road2->road3 of my_graph", isExecutable = false) })
    public static IPath as_path(final IScope scope, final GamaList<IShape> edgesNodes, final GamaGraph graph)
            throws GamaRuntimeException {
        // DEBUG.OUT("Cast.asTopology(scope, graph) : " +
        // Cast.asTopology(scope, graph));
        final IPath path = GamaPathType.staticCast(scope, edgesNodes, null, false);
        path.setGraph(graph);
        return path;

        // return graph.computeShortestPathBetween(sourTarg.key,
        // sourTarg.value);

    }

    /**
     * the comment for all the operators
     */
    static private final String comment = "Available formats: "
            + "\"pajek\": Pajek (Slovene word for Spider) is a program, for Windows, for analysis and visualization of large networks. See: http://pajek.imfm.si/doku.php?id=pajek for more details."
            +
            // "\"dgs_old\", \"dgs\": DGS is a file format allowing to store
            // graphs and dynamic graphs in a textual human readable way, yet
            // with a small size allowing to store large graphs. Graph dynamics
            // is defined using events like adding, deleting or changing a node
            // or edge. With DGS, graphs will therefore be seen as stream of
            // such events. [From GraphStream related page:
            // http://graphstream-project.org/]"+
            "\"lgl\": LGL is a compendium of applications for making the visualization of large networks and trees tractable. See: http://lgl.sourceforge.net/ for more details."
            + "\"dot\": DOT is a plain text graph description language. It is a simple way of describing graphs that both humans and computer programs can use. See: http://en.wikipedia.org/wiki/DOT_language for more details."
            + "\"edge\": This format is a simple text file with numeric vertex ids defining the edges."
            + "\"gexf\": GEXF (Graph Exchange XML Format) is a language for describing complex networks structures, their associated data and dynamics. Started in 2007 at Gephi project by different actors, deeply involved in graph exchange issues, the gexf specifications are mature enough to claim being both extensible and open, and suitable for real specific applications. See: http://gexf.net/format/ for more details."
            + "\"graphml\": GraphML is a comprehensive and easy-to-use file format for graphs based on XML. See: http://graphml.graphdrawing.org/ for more details."
            + "\"tlp\" or \"tulip\": TLP is the Tulip software graph format. See: http://tulip.labri.fr/TulipDrupal/?q=tlp-file-format for more details. "
            + "\"ncol\": This format is used by the Large Graph Layout progra. It is simply a symbolic weighted edge list. It is a simple text file with one edge per line. An edge is defined by two symbolic vertex names separated by whitespace. (The symbolic vertex names themselves cannot contain whitespace.) They might followed by an optional number, this will be the weight of the edge. See: http://bioinformatics.icmb.utexas.edu/lgl for more details."
            + "The map operand should includes following elements:";

    // version depuis un filename avec edge et specy et indication si spatial ou
    // pas

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH,
            IConcept.FILE })
    @doc(value = "returns a graph loaded from a given file encoded into a given format. The last boolean parameter indicates whether the resulting graph will be considered as spatial or not by GAMA", masterDoc = true, comment = comment, usages = {
            @usage(value = "\"format\": the format of the file"),
            @usage(value = "\"filename\": the filename of the file containing the network"),
            @usage(value = "\"edges_species\": the species of edges"),
            @usage(value = "\"vertices_specy\": the species of vertices") }, examples = {
                    @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
                    @example(value = "         \"pajek\",", isExecutable = false),
                    @example(value = "         \"./example_of_Pajek_file\",", isExecutable = false),
                    @example(value = "         myVertexSpecy,", isExecutable = false),
                    @example(value = "         myEdgeSpecy , true);", isExecutable = false) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final String format, final String filename,
            final ISpecies vertex_specy, final ISpecies edge_specy, final Boolean spatial)
            throws GamaRuntimeException {

        return GraphLoader.loadGraph(scope, filename, vertex_specy, edge_specy, null, null, format, spatial);

    }

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "returns a graph loaded from a given file encoded into a given format. This graph will not be spatial.", comment = comment, usages = {
            @usage(value = "\"format\": the format of the file"),
            @usage(value = "\"filename\": the filename of the file containing the network"),
            @usage(value = "\"edges_species\": the species of edges"),
            @usage(value = "\"vertices_specy\": the species of vertices") }, examples = {
                    @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
                    @example(value = "         \"pajek\",", isExecutable = false),
                    @example(value = "         \"./example_of_Pajek_file\",", isExecutable = false),
                    @example(value = "         myVertexSpecy,", isExecutable = false),
                    @example(value = "         myEdgeSpecy);", isExecutable = false) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final String format, final String filename,
            final ISpecies vertex_specy, final ISpecies edge_specy) throws GamaRuntimeException {

        return primLoadGraphFromFile(scope, format, filename, vertex_specy, edge_specy, false);

    }

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "loads a graph from a file", masterDoc = true, usages = @usage(value = "\"filename\": the filename of the file containing the network, \"edges_species\": the species of edges, \"vertices_specy\": the species of vertices", examples = {
            @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
            @example(value = "         \"pajek\",", isExecutable = false),
            @example(value = "         \"./example_of_Pajek_file\",", isExecutable = false),
            @example(value = "         myVertexSpecy,", isExecutable = false),
            @example(value = "         myEdgeSpecy );", isExecutable = false) }))
    public static IGraph primLoadGraphFromFile(final IScope scope, final String filename,
            final ISpecies vertex_specy, final ISpecies edge_specy) throws GamaRuntimeException {

        return primLoadGraphFromFile(scope, null, filename, vertex_specy, edge_specy);

    }

    // version depuis un file avec edge et specy

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = @usage(value = "\"format\": the format of the file, \"file\": the file containing the network, \"edges_species\": the species of edges, \"vertices_specy\": the species of vertices", examples = {
            @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
            @example(value = "         \"pajek\",", isExecutable = false),
            @example(value = "         \"example_of_Pajek_file\",", isExecutable = false),
            @example(value = "         myVertexSpecy,", isExecutable = false),
            @example(value = "         myEdgeSpecy );", isExecutable = false) }))
    public static IGraph primLoadGraphFromFile(final IScope scope, final String format, final GamaFile gamaFile,
            final ISpecies vertex_specy, final ISpecies edge_specy) throws GamaRuntimeException {
        return primLoadGraphFromFile(scope, gamaFile.getPath(scope), vertex_specy, edge_specy);

    }

    // version depuis un filename sans edge et sans specy

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = {
            @usage(value = "\"format\": the format of the file, \"filename\": the filename of the file containing the network", examples = {
                    @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
                    @example(value = "         \"pajek\",", isExecutable = false),
                    @example(value = "         \"example_of_Pajek_file\");", isExecutable = false) }) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final String format, final String filename)
            throws GamaRuntimeException {
        // AD 29/09/13: Changed the previous code that was triggering an
        // overflow.
        return primLoadGraphFromFile(scope, format, filename, null, null);
    }

    // version depuis un file avec edge et specy

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = {
            @usage(value = "\"format\": the format of the file, \"file\": the file containing the network", examples = {
                    @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
                    @example(value = "         \"pajek\",", isExecutable = false),
                    @example(value = "         \"example_of_Pajek_file\");", isExecutable = false) }) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final String format, final GamaFile gamaFile)
            throws GamaRuntimeException {
        // AD 29/09/13 : Simply called the previous method with the path of the
        // file. Not efficient, but should work.
        return primLoadGraphFromFile(scope, format, gamaFile.getPath(scope));
        // throw GamaRuntimeException.error("not implemented: loading from gama
        // file");

    }

    @operator(value = "load_graph_from_file", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(usages = { @usage(value = "\"file\": the file containing the network", examples = {
            @example(value = "graph<myVertexSpecy,myEdgeSpecy> myGraph <- load_graph_from_file(", isExecutable = false),
            @example(value = "         \"pajek\",", isExecutable = false),
            @example(value = "         \"example_of_Pajek_file\");", isExecutable = false) }) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final String filename)
            throws GamaRuntimeException {
        return primLoadGraphFromFile(scope, null, filename);
    }

    /*
     * public static IGraph addRandomEdges(final IGraph g, final Double probability) {
     * GraphAlgorithmsHandmade.rewireGraph(g, probability); return g; }
     */

    @operator(value = "load_shortest_paths", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1, category = { IOperatorCategory.GRAPH,
                    IOperatorCategory.PATH }, concept = { IConcept.GRAPH, IConcept.SHORTEST_PATH })
    @doc(value = "put in the graph cache the computed shortest paths contained in the matrix (rows: source, columns: target)", examples = {
            @example(value = "load_shortest_paths(shortest_paths_matrix)", equals = "return my_graph with all the shortest paths computed", isExecutable = false) })
    public static IGraph primLoadGraphFromFile(final IScope scope, final GamaGraph graph, final GamaMatrix matrix)
            throws GamaRuntimeException {
        if (graph == null) {
            throw GamaRuntimeException.error("In the load_shortest_paths operator, the graph should not be null!",
                    scope);
        }
        // final int n = graph.vertexSet().size();
        graph.loadShortestPaths(scope, matrix);
        return graph;
        // throw GamaRuntimeException.error("not implemented: loading from gama
        // file");

    }

    @operator(value = "all_pairs_shortest_path", type = IType.MATRIX, content_type = IType.INT, category = {
            IOperatorCategory.GRAPH, IOperatorCategory.PATH }, concept = { IConcept.GRAPH, IConcept.SHORTEST_PATH })
    @doc(value = "returns the successor matrix of shortest paths between all node pairs (rows: source, columns: target): a cell (i,j) will thus contains the next node in the shortest path between i and j.", examples = {
            @example(value = "all_pairs_shortest_paths(my_graph)", equals = "shortest_paths_matrix will contain all pairs of shortest paths", isExecutable = false) })
    public static GamaIntMatrix primAllPairShortestPaths(final IScope scope, final GamaGraph graph)
            throws GamaRuntimeException {
        if (graph == null) {
            throw GamaRuntimeException
                    .error("In the all_pairs_shortest_paths operator, the graph should not be null!", scope);
        }
        return graph.saveShortestPaths(scope);
    }

    @operator(value = "layout", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX
                    + 1, category = { IOperatorCategory.GRAPH }, concept = { IConcept.GRAPH })
    @doc(value = "layouts a GAMA graph.", masterDoc = true)
    // TODO desc
    public static IGraph layoutOneshot(final IScope scope, final GamaGraph graph, final String layoutEngine,
            final int timeout, final GamaMap<String, Object> options) {

        // translate Gama options to
        Map<String, Object> jOptions = null;
        if (options.isEmpty()) {
            jOptions = Collections.EMPTY_MAP;
        } else {
            jOptions = new HashMap<>(options.size());
            for (final String key : options.keySet()) {
                jOptions.put(key, options.get(scope, key));
            }
        }
        AvailableGraphLayouts
                // retrieve layout for he layout that was selected by the user
                // (may raise an exception)
                .getStaticLayout(scope, layoutEngine.trim().toLowerCase())
                // apply this layout with the options
                .doLayoutOneShot(scope, graph, timeout, jOptions);

        return graph;
    }

    @operator(value = "layout", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX
            + 1, index_type = ITypeProvider.KEY_TYPE_AT_INDEX + 1,

            category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "layouts a GAMA graph.")
    public static IGraph layoutOneshot(final IScope scope, final GamaGraph graph, final String layoutEngine,
            final int timeout) {
        return layoutOneshot(scope, graph, layoutEngine, timeout,
                GamaMapFactory.create(Types.STRING, Types.NO_TYPE));
    }

    @operator(value = "layout", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "layouts a GAMA graph.")
    public static IGraph layoutOneshot(final IScope scope, final GamaGraph graph, final String layoutEngine) {
        return layoutOneshot(scope, graph, layoutEngine, -1);
    }

    @operator(value = "adjacency", category = { IOperatorCategory.GRAPH }, concept = {})
    @doc(value = "adjacency matrix of the given graph.")
    public static GamaFloatMatrix adjacencyMatrix(final IScope scope, final GamaGraph graph) {
        return graph.toMatrix(scope);
    }

    @operator(value = "strahler", content_type = ITypeProvider.CONTENT_TYPE_AT_INDEX + 1, category = {
            IOperatorCategory.GRAPH, IConcept.EDGE })
    @doc(value = "retur for each edge, its strahler number")
    public static GamaMap strahlerNumber(final IScope scope, final GamaGraph graph) {
        final GamaMap<Object, Integer> results = GamaMapFactory.create(Types.NO_TYPE, Types.INT);
        if (graph == null || graph.isEmpty(scope)) {
            return results;
        }
        if (!graph.getConnected() || graph.hasCycle()) {
            throw GamaRuntimeException
                    .error("Strahler number can only be computed for Tree (connected graph with no cycle)!", scope);
        }

        List currentEdges = (List) graph.getEdges().stream()
                .filter(a -> graph.outDegreeOf(graph.getEdgeTarget(a)) == 0).collect(Collectors.toList());
        while (!currentEdges.isEmpty()) {
            final List newList = new ArrayList<>();
            for (final Object e : currentEdges) {
                final List previousEdges = inEdgesOf(scope, graph, graph.getEdgeSource(e));
                final List nextEdges = outEdgesOf(scope, graph, graph.getEdgeTarget(e));
                if (nextEdges.isEmpty()) {
                    results.put(e, 1);
                    newList.addAll(previousEdges);
                } else {
                    final boolean notCompleted = nextEdges.stream().anyMatch(a -> !results.containsKey(a));
                    if (notCompleted) {
                        newList.add(e);
                    } else {
                        final List<Integer> vals = (List<Integer>) nextEdges.stream().map(a -> results.get(a))
                                .collect(Collectors.toList());
                        final Integer maxVal = Collections.max(vals);
                        final int nbIt = Collections.frequency(vals, maxVal);
                        if (nbIt > 1) {
                            results.put(e, maxVal + 1);
                        } else {
                            results.put(e, maxVal);
                        }
                        newList.addAll(previousEdges);
                    }
                }
            }
            currentEdges = newList;
        }
        return results;
    }

    // TODO "complete" (pour crer un graphe complet)

    // vertices_to_graph [vertices] with_weights (vertices collect: each.val) ->
    // renvoie un graphe
    // construit  partir des vertex (edges gnrs soit sous la forme d'une
    // paire vertex::vertex,
    // soit sous la forme d'un lien gomtrique)
    // vertices_to_graph [a1, a2, a3] with_weights ([1, 4, 8]) -> mme chose
    // edges_to_graph [edges] with_weights (edges collect: each.length) ->
    // renvoie un graphe
    // construit  partir des edges (vertex gnrs soit sous la forme d'une
    // paire edge::edge, soit
    // sous la forme d'un point pour les gomtries)
    // edges_to_graph [a1::a2, a2::a3] with_weights ([3.0, 1.3]) -> mme chose
    // add item: v1 to:g weight: 1 -> ajout d'un vertex
    // add item: v1::v2 to:g weight:1 -> ajout d'un edge gnr (et des vertex
    // correspondants si
    // ncessaire)
    // add item: (v1::v2)::e to: g weight: 1 -> edge (ajout d'un edge explicite
    // et des vertex
    // correspondants si ncessaire)
    // remove item: v1::v2 from: g -> remove edge
    // remove item: o from: g -> remove edge / vertex
    // put item: e2 at: v1::v2 in: g -> replace/add an edge (on peut aussi faire
    // la mme chose pour
    // remplacer un vertex)

    // TODO Transformer peu  peu toutes les primitives (GeometricFunctions,
    // GeometricSkill, etc.)
    // en oprateurs (as_graph, as_network, as_triangle_graph, as_complete_graph
    // -- En crant les
    // liens dynamiques correspondants --, as_weighted_graph ...).

    // TODO Ajouter les oprateurs d'union, d'intersection, d'galit, de
    // diffrence

    // TODO Ajouter des gnrateurs spcifiques a partir de GraphGenerator (pb:
    // quelles classes pour
    // les vertices/edges ??

}