true if any end of this edge fulfills pred.

true if node is incident with this edge.

A function to determine whether the arity of the passed Product of nodes (that is the number of edge ends) is valid. This function is called on every edge-instantiation by validate that throws EdgeException if this method returns false.

Iterator for the nodes (end-points) of this edge.

The end nodes joined by this edge.

Nodes will typically be represented by Tuples. Alternatively subclasses of Iterable implementing Product, such as List, may also be used. In the latter case be aware of higher memory footprint.

The first node. Same as _n(0).

The second node. Same as _n(1).

The n'th node with 0 <= n < arity.

Number of nodes linked by this Edge. At least two nodes are linked. In case of a hook, the two nodes are identical. Hyperedges may link more than two nodes.

Same as isAt.

true if this edge is directed.

Preconditions: this.directed == that.directed && this.isInstanceOf[Keyed] == that.isInstanceOf[Keyed]

Synonym for source.

true if any source end of this edge fulfills pred.

true if node is a source of this edge. In case this edge is undirected this method maps to isAt.

true if any target end of this edge fulfills pred.

true if node is a target of this edge. In case this edge is undirected this method maps to isAt.

Same as directed.

true if this is a hyperedge that is it may have more than two ends.

true if this edge is labeled. See also label.

true if this edge produces a self-loop. In case of a non-hyperedge, a loop is given if the incident nodes are equal. In case of a directed hyperedge, a loop is given if the source is equal to any of the targets. In case of an undirected hyperedge, a loop is given if any pair of incident nodes has equal nodes.

Same as undirected.

This method may be overridden to enforce additional validation at edge creation time. Be careful to call super.isValidCustom when overriding. This function is called on every edge-instantiation by validate that throws EdgeException if this method returns false.

The label of this edge. If Graph's edge type parameter has been inferred or set to a labeled edge type all contained edges are labeled. Otherwise you should assert, for instance by calling isLabeled, that the edge instance is labeled before calling this method.

Note that label is normally not part of the edge key (hashCode). As a result, edges with different labels connecting the same nodes will be evaluated as equal and thus added once and only once to the graph. In case you need multi-edges based on different labels you should either make use of a predefined key-labeled edge type such as LDiEdge or define a custom edge class that mixes in ExtendedKey and adds label to keyAttributes.

true if
a) two distinct ends of this undirected edge exist for which p1 and p2 hold or
b) p1 holds for a source and p2 for a target of this directed edge.

true if
a) both n1 and n2 are at this edge for an undirected edge
b) n1 is a source and n2 a target of this edge for a directed edge.

Sequence of the end points of this edge.

true if this edge has exactly two ends.

Same as ! looping.

The single source node of this directed edge.

All source ends of this edge.

The target node for a directed edge; one of the target nodes for a directed hyperedge.

All target ends of this edge.

Synonym for target.

true if this edge is undirected.

Performs basic, inevitable edge validation. Among others, ensures that nodes ne null and no edge end eq null.

This validation method must be called in the constructor of any edge class that directly extends or mixes in EdgeLike. To perform additional custom validation isValidCustom is to be overridden.

The weight of this edge with a default of 1.

Note that weight is normally not part of the edge key (hashCode). As a result, edges with different weights connecting the same nodes will be evaluated as equal and thus added once and only once to the graph. In case you need multi-edges based on different weights you should either make use of a predefined key-weighted edge type such as WDiEdge or define a custom edge class that mixes in ExtendedKey and adds weight to keyAttributes.

Applies f to all source ends of this edge without any memory allocation.

Applies f to the target ends of this edge without any memory allocation.