pylibhipgraph.induced_subgraph

2025-05-20

2 min read time

Applies to Linux

induced_subgraph (ResourceHandle resource_handle, _GPUGraph graph, subgraph_vertices, subgraph_offsets, bool_t do_expensive_check)

extract a list of edges that represent the subgraph containing only the specified vertex ids.

Parameters

resource_handleResourceHandle

Handle to the underlying device resources needed for referencing data and running algorithms.

graphSGGraph or MGGraph

The input graph.

subgraph_verticescupy array

array of vertices to include in extracted subgraph.

subgraph_offsetscupy array

array of subgraph offsets into subgraph_vertices.

do_expensive_checkbool_t

If True, performs more extensive tests on the inputs to ensure validitity, at the expense of increased run time.

Returns

A tuple of device arrays containing the sources, destinations, edge_weights and the subgraph_offsets(if there are more than one seeds)

Examples

>>> import pylibhipgraph, cupy, numpy
>>> srcs = cupy.asarray([0, 1, 1, 2, 2, 2, 3, 4], dtype=numpy.int32)
>>> dsts = cupy.asarray([1, 3, 4, 0, 1, 3, 5, 5], dtype=numpy.int32)
>>> weights = cupy.asarray(
...     [0.1, 2.1, 1.1, 5.1, 3.1, 4.1, 7.2, 3.2], dtype=numpy.float32)
>>> subgraph_vertices = cupy.asarray([0, 1, 2, 3], dtype=numpy.int32)
>>> subgraph_offsets = cupy.asarray([0, 4], dtype=numpy.int32)
>>> resource_handle = pylibhipgraph.ResourceHandle()
>>> graph_props = pylibhipgraph.GraphProperties(
...     is_symmetric=False, is_multigraph=False)
>>> G = pylibhipgraph.SGGraph(
...     resource_handle, graph_props, srcs, dsts, weight_array=weights,
...     store_transposed=False, renumber=False, do_expensive_check=False)
>>> (sources, destinations, edge_weights, subgraph_offsets) =
...     pylibhipgraph.induced_subgraph(
...         resource_handle, G, subgraph_vertices, subgraph_offsets, False)
>>> sources
[0, 1, 2, 2, 2]
>>> destinations
[1, 3, 0, 1, 3]
>>> edge_weights
[0.1, 2.1, 5.1, 3.1, 4.1]
>>> subgraph_offsets
[0, 5]