Heterogeneous Graph Degree

Problem

Compute the total degree of each node type in a heterogeneous graph.

nodes_types[i] is the type string of node i and typed_edges is a list of [u, v, type] triples. Each edge contributes one incidence to each endpoint's degree. Return a dictionary mapping each node type to the sum of degrees of its nodes.

Hint

Type-level degree sums aggregate the activity of each node class.

Test cases

case 1

in: [["user","user","item","item"],[[0,2,"buy"],[1,2,"buy"],[0,3,"view"]]]

expected: {"user":3,"item":3}

case 2

in: [["a","b","a"],[[0,1,"x"],[1,2,"y"]]]

expected: {"a":2,"b":2}

case 3

in: [["x"],[]]

expected: {"x":0}

Starter codePython

def heterogeneous_degree(node_types, typed_edges):
    # Your code here
    pass

3 test cases · run your code against them in the editor