# triangles#

triangles(G, nodes=None)[source]#

Compute the number of triangles.

Finds the number of triangles that include a node as one vertex.

Parameters:
Ggraph

A networkx graph

nodesnode, iterable of nodes, or None (default=None)

If a singleton node, return the number of triangles for that node. If an iterable, compute the number of triangles for each of those nodes. If `None` (the default) compute the number of triangles for all nodes in `G`.

Returns:
outdict or int

If `nodes` is a container of nodes, returns number of triangles keyed by node (dict). If `nodes` is a specific node, returns number of triangles for the node (int).

Notes

Self loops are ignored.

Examples

```>>> G = nx.complete_graph(5)
>>> print(nx.triangles(G, 0))
6
>>> print(nx.triangles(G))
{0: 6, 1: 6, 2: 6, 3: 6, 4: 6}
>>> print(list(nx.triangles(G, [0, 1]).values()))
[6, 6]
```

Additional backends implement this function

cugraph : GPU-accelerated backend.

graphblas : OpenMP-enabled sparse linear algebra backend.