When merging nodes with:
apoc.refactor.mergeNodes(nodes, {properties:'combine', mergeRels:true})
The nodes' relationships will be merged as well, and their properties will be concatenated in a list:
(merged_nodes)-[merged_edges]-()
merged_edges.weight = [2,4,6]
Instead of a list I want an average
merged_edges.weight = avg([2,4,6]) = 4
How can I do that?