neighbor command

Syntax:

neighbor -i in1 -o out1.file out1.mr 

• in1 = graph edges: Key = Vi Vj, Value = NULL
• out1 = neighbors of each vertex: Key = Vi, Value = Vj Vk ...

Examples:

degree -i mrv -o degree.list NULL

Description:

This is a named command which calculates the list of neighbors of each vertex in an undirected graph. A list of all the vertices each vertex shares an edge with is calculated. These are the first neighbors of each vertex.

See the named command doc page for various ways in which the -i inputs and -o outputs for a named command can be specified.

In1 stores a set of edges, assumed to have no duplicates or self-edges. This means that either (Vi,Vj) or (Vj,Vi) appears, but not both. Also (Vi,Vi) does not appear. The input is unchanged by this command.

Out1 will store the list of neighbor vertices for each vertex. The list is a single value in a key/value pair which is a vector of vertex IDs, one after the other.

Related commands:

degree, neigh_tri