Neo4j 中的随机游走不输出（默认）预期的游走次数

Question

我正在提取一个只有 4 个节点的简单图，所有节点都连接在一起，这意味着没有孤立的节点，并且它们中的任意两个节点之间都有一条路径。那我就是运行一个随机游走算法。然而，该算法仅输出两次行走，而从技术上讲它应该是四次——每个节点一次。不确定是什么问题，我们将不胜感激。这是代码-

// Cypher query to extract the subgraph with 4 nodes - any two have a path

MATCH p=(m1)-[r]->(m2) 
WHERE (m1 IN events AND m2 IN events)
WITH COLLECT(m1) AS m1s, COLLECT(m2) AS m2s, COLLECT({source:m1, target:m2, type: TYPE(r)}) AS rels 

// Create a projection

WITH apoc.coll.toSet(m1s + m2s) AS nodes, rels

CALL gds.graph.create.cypher(
  "example",
   "UNWIND $nodes AS n RETURN id(n) AS id, labels(n) AS labels",
   "UNWIND $rels AS rel RETURN id(rel['source']) AS source , id(rel['target']) AS target, 
   { LINKS: { orientation: 'UNDIRECTED' } }, rel['type'] AS type", 
   {parameters: {nodes:nodes, rels:rels} }

YIELD graphName AS graph, nodeQuery, 
      nodeCount AS nodes_count, relationshipQuery, 
      relationshipCount AS rels_count

// Call the Random Walk algorithm

CALL gds.beta.randomWalk.stream(
  'example',
  {
    walkLength: 3,
    walksPerNode: 1,
    randomSeed: 42,
    concurrency: 1
  }
)

YIELD nodeIds, path

RETURN nodeIds, [node IN nodes(path) | node.name ] AS event_name

Answer 1

根据@micro5 的建议（见上面的评论）我替换了语句：

MATCH p=(m1)-[r]->(m2) 和 MATCH p=(m1)-[r]-(m2) 并且随机游走按预期执行。

Neo4j 中的随机游走不输出（默认）预期的游走次数

Random walk in Neo4j doesn't output (default) expected number of walks

neo4j

cypher

random-walk