def consensus(splits, taxon_namespace, q=0.5):
"""Creates a consensus tree from a dictionary of splits w/ credibilities (default is majority-rule consensus).
Splits are added to the tree in order of decreasing credibility. A split is added if:
1. Its credibility is >= q
2. It is compatible with all preceding splits
The edges of the returned tree are annotated with their split's credibilities.
"""
# Order and select splits
sorted_splits = sorted(splits.items(), key=op.itemgetter(1), reverse=True)
selected_splits = map(op.itemgetter(0), it.takewhile(lambda x: x[1] >= q, sorted_splits))
# Dendropy handles dropping of incompatible splits
tree = Tree.from_bipartition_encoding(selected_splits, taxon_namespace)
# Annotate edges with credibilities
for edge in tree.edges():
edge.annotations.add(Annotation('cred', splits[edge.bipartition]))
return tree
