Source code for graphscope.analytical.app.is_simple_path

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
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# Copyright 2020 Alibaba Group Holding Limited. All Rights Reserved.
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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#     http://www.apache.org/licenses/LICENSE-2.0
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# Author: Ma JingYuan<nn9902@qq.com>
#

import json

from graphscope.framework.app import AppAssets
from graphscope.framework.app import not_compatible_for
from graphscope.framework.app import project_to_simple

__all__ = ["is_simple_path"]


[docs]@project_to_simple @not_compatible_for("arrow_property") def is_simple_path(graph, nodes): """Returns True if and only if `nodes` form a simple path in `G`. A *simple path* in a graph is a nonempty sequence of nodes in which no node appears more than once in the sequence, and each adjacent pair of nodes in the sequence is adjacent in the graph. Parameters ---------- graph (:class:`graphscope.Graph`): A simple graph. nodes : list A list of one or more nodes in the graph `G`. Returns ------- bool Whether the given list of nodes represents a simple path in `G`. Notes ----- An empty list of nodes is not a path but a list of one node is a path. Here's an explanation why. This function operates on *node paths*. One could also consider *edge paths*. There is a bijection between node paths and edge paths. The *length of a path* is the number of edges in the path, so a list of nodes of length *n* corresponds to a path of length *n* - 1. Thus the smallest edge path would be a list of zero edges, the empty path. This corresponds to a list of one node. To convert between a node path and an edge path, you can use code like the following:: >>> from networkx.utils import pairwise >>> nodes = [0, 1, 2, 3] >>> edges = list(pairwise(nodes)) >>> edges [(0, 1), (1, 2), (2, 3)] >>> nodes = [edges[0][0]] + [v for u, v in edges] >>> nodes [0, 1, 2, 3] Examples -------- .. code:: python >>> import graphscope >>> from graphscope.dataset import load_p2p_network >>> sess = graphscope.session(cluster_type="hosts", mode="eager") >>> g = load_p2p_network(sess) >>> # project to a simple graph (if needed) >>> pg = g.project(vertices={"host": ["id"]}, edges={"connect": ["dist"]}) >>> c = graphscope.is_simple_path(pg, [2, 3, 8]) >>> print(c) >>> sess.close() """ if isinstance(nodes, list): n1json = json.dumps(nodes) ctx = AppAssets(algo="is_simple_path", context="tensor")(graph, n1json) return ctx.to_numpy("r", axis=0)[0] raise ValueError("input nodes is not a list object!")