Analytical App

AppAssets

class graphscope.framework.app.AppAssets(algo, gar=None, **kwargs)

A class holds the bytes of the gar resource.

Assets includes name (for builtin algorithm), and gar (for user defined algorithm), and its type (one of cpp_pie, cython_pie, cython_pregel.

The instance of this class can be passed to init graphscope.App.

algo

Name of the algorithm

Type

str

type

Type of the algorithm

Type

str

gar

Byte content of user defined algorithm

Type

bytes

signature

Unique identifier of this assets.

Type

str

__init__(algo, gar=None, **kwargs)

Init assets of the algorithm.

Parameters

• algo (str) – Represent specific algo inside resource.

• gar (bytes or BytesIO, optional) – The bytes that encodes the application’s source code. Default to None

• kwargs – Other params, e.g. vd_type and md_type in cython app.

__weakref__

list of weak references to the object (if defined)

property algo

Algorithm name, e.g. sssp, pagerank.

Returns

Algorithm name of this asset.

Return type

str

property gar

Gar resource.

Returns

gar resource of this asset.

Return type

bytes

is_compatible(graph)

Determine if this algorithm can run on this type of graph.

Parameters

graph (Graph) – A graph instance.

Raises

• InvalidArgumentError –

  • gs_conf.yaml not exist in gar resource. - App is not compatible with graph or - Algo not found in gar resource.

• ScannerError –

  • Yaml file format is incorrect.

property signature

Generate a signature of the app assets by its algo name (and gar resources).

Used to uniquely identify a app assets. :returns: signature of this assets :rtype: str

property type

Algorithm type, one of cpp_pie, cython_pie or cython_pregel.

Returns

Algorithm type of this asset.

Return type

str

BuiltIn apps

graphscope.bfs(graph, src=0)

Breadth first search from the src on projected simple graph.

Parameters

• graph (Graph) – A projected simple graph.

• src (int, optional) – Source vertex of breadth first search. Defaults to 0.

Returns

a context with each vertex with a distance from the source.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.bfs(pg, 6)  # use 6 as source vertex
s.close()

graphscope.pagerank(graph, delta=0.85, max_round=10)

Evalute PageRank on a graph.

Parameters

• graph (Graph) – A projected simple graph.

• delta (float, optional) – Dumping factor. Defaults to 0.85.

• max_round (int, optional) – Maximum number of rounds. Defaults to 10.

Returns

A context with each vertex assigned with the pagerank value.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.k_core(pg, delta=0.85, max_round=10)
s.close()

graphscope.sssp(graph, src=0)

Compute single source shortest path on the graph.

Parameters

• graph (Graph) – A projected simple graph.

• src (int, optional) – The source vertex. Defaults to 0.

Returns

A context with each vertex assigned with the shortest distance from the src.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel', v_prop=None, e_prop='distance')
r = gs.sssp(pg, src=0)
s.close()

graphscope.wcc(graph)

Evaluate weakly connected components on the graph.

Parameters

graph (Graph) – A projected simple graph.

Returns

A context with each vertex assigned with the component ID.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.wcc(pg)
s.close()

graphscope.cdlp(graph, max_round=10)

Evaluate Community Detection with Label Propagation.

Parameters

• graph (Graph) – A projected simple graph.

• max_round (int, optional) – Maximum rounds. Defaults to 10.

Returns

A context with each vertex assigned with a community ID.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.cdlp(g, max_round=10)
s.close()

graphscope.clustering(graph)

Local clustering coefficient of a node in a Graph is the fraction of pairs of the node’s neighbors that are adjacent to each other.

Parameters

graph (Graph) – A projected simple graph.

Returns

A context with each vertex assigned the computed clustering value.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.clustering(pg)
s.close()

graphscope.degree_centrality(graph, centrality_type='both')

The degree centrality values are normalized by dividing by the maximum possible degree in a simple graph n-1 where n is the number of nodes in G.

Parameters

• graph (Graph) – A projected simple graph.

• centrality_type (str, optional) – Available options are in/out/both. Defaults to “both”.

Returns

A context with each vertex assigned with the computed degree centrality.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label="vlabel", e_label="elabel")
r = gs.degree_centrality(pg, centrality_type="both")
s.close()

graphscope.eigenvector_centrality(graph, tolerance=1e-06, max_round=100)

Compute the eigenvector centrality for the graph. See more about eigenvector centrality here: https://networkx.org/documentation/networkx-1.10/reference/generated/networkx.algorithms.centrality.eigenvector_centrality.html

Parameters

• graph (Graph) – A projected simple graph.

• tolerance (float, optional) – Defaults to 1e-06.

• max_round (int, optional) – Defaults to 100.

Returns

A context with each vertex assigned with a gv-centrality.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.eigenvector_centrality(pg)
s.close()

graphscope.hits(graph, tolerance=0.01, max_round=100, normalized=True)

Compute HITS on graph.

Hyperlink-Induced Topic Search (HITS; also known as hubs and authorities) is a link analysis algorithm that rates Web pages. See more here: https://en.wikipedia.org/wiki/HITS_algorithm

Parameters

• graph (Graph) – A projected simple graph.

• tolerance (float, optional) – Defaults to 0.01.

• max_round (int, optional) – Defaults to 100.

• normalized (bool, optional) – Whether to normalize the result to 0-1. Defaults to True.

Returns

A context with each vertex assigned with the HITS value.

Return type

VertexPropertyContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.hits(pg)
s.close()

graphscope.k_core(graph, k: int)

K-cores of the graph are connected components that are left after all vertices of degree less than k have been removed.

Parameters

• graph (Graph) – A projected simple graph.

• k (int) – The k for k-core.

Returns

A context with each vertex assigned with a boolean: 1 if the vertex satisfies k-core, otherwise 0.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.k_core(pg)
s.close()

graphscope.katz_centrality(graph, alpha=0.1, beta=1.0, tolerance=1e-06, max_round=100, normalized=True)

Compute the Katz centrality.

See more details for Katz centrality here: https://networkx.org/documentation/stable/reference/algorithms/generated/networkx.algorithms.centrality.katz_centrality_numpy.html

Parameters

• graph (Graph) – A projected simple graph.

• alpha (float, optional) – Auttenuation factor. Defaults to 0.1.

• beta (float, optional) – Weight attributed to the immediate neighborhood. Defaults to 1.0.

• tolerance (float, optional) – Error tolerance. Defaults to 1e-06.

• max_round (int, optional) – Maximun number of rounds. Defaults to 100.

• normalized (bool, optional) – Whether to normalize result values. Defaults to True.

Returns

A context with each vertex assigned with the computed katz_centrality.

Return type

VertexDatacontext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.katz_centrality(pg)
s.close()

graphscope.lpa(graph, max_round=10)

Evaluate (multi-) label propagation on a property graph.

Parameters

• graph (Graph) – A property graph.

• max_round (int, optional) – Maximum number of rounds. Defaults to 10.

Returns

A context with each vertex, following an array of propagated labels.

Return type

LabeledVertexPropertyContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
r = gs.lpa(g)
s.close()

graphscope.triangles(graph)

Evaluate triangle counting of the graph G.

Parameters

graph (Graph) – A projected simple graph.

Returns

A context with each vertex assigned with the triangle counting result.

Return type

VertexDataContext

Examples:

import graphscope as gs
s = gs.session()
g = s.load_from('The parameters for loading a graph...')
pg = g.project_to_simple(v_label='vlabel', e_label='elabel')
r = gs.triangles(pg)
s.close()

App object

class graphscope.framework.app.App(graph, app_assets: graphscope.framework.app.AppAssets)

An application that can run on graphs and produce results.

Analytical engine will build the app dynamic library when instantiate a app instance. The dynamic library will be reused if subsequent app’s signature matches one of previous ones.

key

Identifier of the app, associated with the dynamic library path. set by analytical engine after library is built.

Type

str

signature

Combination of app_assets’s and graph’s signature.

Type

str

session_id

Session id of the session that associated with the app.

Type

str

algo

Algorithm name of app_assets.

Type

str

gar

Gar content of app_assets.

Type

str

__init__(graph, app_assets: graphscope.framework.app.AppAssets)

Create an application using given gar file, or given application

class name.

Parameters

• graph (Graph) – A Graph instance.

• app_assets – A AppAssets instance.

Raises

TypeError – The type of app_assets incorrect.

__weakref__

list of weak references to the object (if defined)

property algo

Algorithm name, e.g. sssp, pagerank.

Returns

Algorithm name of this asset.

Return type

str

property gar

Gar resource.

Returns

gar resource of this asset.

Return type

bytes

property key

A unique identifier of App.

loaded()

Since key is only set by engine after it load the app, and unset to None when unload,

we can use the key to detect whether the app is loaded.

Returns

The app is loaded or not.

Return type

bool

property session_id

Return the session_id, which is copied from the graph.

Returns

Id of the session which loaded the app.

Return type

str

property signature

Signature is computed by all critical components of the App.

unload()

Unload app. Both on engine side and python side. Set the key to None.

Functions

graphscope.framework.app.load_app(algo[, gar])

Load an app from gar.