def build_graph_from_vectors(vector_set, show_subgraph=False):
"creates top-level fraph from set of vectors"
B = nx.Graph()
for fno, hset in vector_set:
B.add_node(FnameMap.encode(fno), bipartite=0)
for hno in hset:
if hno not in B:
B.add_node(ChecksumMap.encode(hno), bipartite=1)
B.add_edge(FnameMap.encode(fno), ChecksumMap.encode(hno))
return B
