Argument | Category | Description |
---|---|---|
TargetKey | Required | Specifies the key of the target vertex of an edge. The key consists of the names of one or more edges table columns. |
Directed | Optional | Legacy argument that determined whether the graph was directed. The default value was 'true'. The function ignores this argument, treating all graphs as undirected. |
EdgeWeight | Optional | Specifies the name of the edges table column that contains edge weights. Each edge_weight is a positive values. By default, the weight of each edge is 1 (that is, the graph is unweighted). This argument determines how the function treats duplicate edges (that is, edges with the same source and destination, which might have different weights). For a weighted graph, the function treats duplicate edges as a single edge whose weight is the sum of the weights of the duplicate edges. For an unweighted graph, the function uses only one of the duplicate edges. |
CommunityAssociation | Optional | Specifies the name of the column that represents the community association of the vertices. Use this argument if you already know some vertex communities. |
Resolution | Optional | Specifies hierarchical-level information for the communities. For details, refer to Resolution. The default resolution is 1.0. If you specify a list of resolution values, the function incrementally finds the communities for each value and for the default value. Each resolution must be a distinct DOUBLE PRECISION value in the range [0.0, 1000000.0]. The value 0.0 puts each node in its own community of size 1. You can specify a maximum of 500 resolution values. To get the modularity of more than 500 resolution points, call the function multiple times, specifying different values in each call. |
CommunityEdgeTable | Optional | Specifies the name of the table that the function generates to output the weights of the edges between the communities at different resolution levels. If a table named community_edge_table exists, the function overwrites the existing table. If you omit this argument, the function does not create this table. |
Seed | Optional | Specifies the seed to use to create a random number during modularity computation. The seed must be a positive BIGINT value. The function multiplies seed by the hash code of vertex_key to generate a unique seed for each vertex. The default seed is 1. The seed significantly impacts community formation (and modularity score), because the function uses seed for these purposes:
Deeper analysis of the graph can improve community formation, but can also increase execution time. |
Accumulate | Optional | Specifies the names of the vertices columns to copy to the community vertex table. By default, the function copies the vertex_key columns to the output vertex table for each vertex, changing the column names to id, id_1, id_2, and so on. |