analyze.h File Reference

Provides basic network analysis and adds them to the graph output. More...

Go to the source code of this file.

Functions
int	calc_betweenness (igraph_t *graph)
int	calc_authority (igraph_t *graph)
int	calc_hub (igraph_t *graph)
int	calc_pagerank (igraph_t *graph)
int	calc_eigenvector (igraph_t *graph)
int	calc_degree (igraph_t *graph, char type)
int	calc_modularity (igraph_t *graph)
int	centralization (igraph_t *graph, char *attr)
int	analysis_all (igraph_t *graph)

Detailed Description

Provides basic network analysis and adds them to the graph output.

Analyze.h contains the main functions for analysing network graphs. These functions are used by other files (filter, or viz, for instance) to determine such things as what to filter, how to produce colors, and what size nodes should be.

Function Documentation

analysis_all()

int analysis_all

(

igraph_t *

graph

)

Calculates the main analysis scores for the graph

analysis_all conducts all available graph, node and edge scores available in the network utility. It is very expensive in terms of processing time, so should be used only for smaller graphs.

Parameters

graph

- the graph for which to record the scores.

calc_authority()

int calc_authority

(

igraph_t *

graph

)

Calculates authority scores for the individual nodes in a graph

Authority is measured

Parameters

graph

- the graph for which to record the scores.

calc_betweenness()

int calc_betweenness

(

igraph_t *

graph

)

Calculates betweenness scores for the individual nodes in a graph

Betweenness is measured

Parameters

graph

- the graph for which to record the scores.

Returns

0 unless error occurs.

calc_degree()

int calc_degree	(	igraph_t *	graph,
		char	type
	)

Calculates degree scores for the individual nodes in a graph

Authority is measured

Parameters

graph	- the graph for which to record the scores.
type	- 'i' for indegree, 'o' for outdegree, 'd' for degree

calc_eigenvector()

int calc_eigenvector

(

igraph_t *

graph

)

Calculates eigenvector centrality scores for the individual nodes in a graph

Authority is measured

Parameters

graph

- the graph for which to record the scores.

calc_hub()

int calc_hub

(

igraph_t *

graph

)

Calculates hub scores for the individual nodes in a graph

Hub is measured

Parameters

graph

- the graph for which to record the scores.

calc_modularity()

int calc_modularity

(

igraph_t *

graph

)

Calculates walktrap modularity scores for the individual nodes in a graph and sets group values for each.

Walktrap modularity is measured

Parameters

graph

- the graph for which to record the scores.

calc_pagerank()

int calc_pagerank

(

igraph_t *

graph

)

Calculates pagerank scores for the individual nodes in a graph

Pagerank is measured

Parameters

graph

- the graph for which to record the scores.

centralization()

int centralization	(	igraph_t *	graph,
		char *	attr
	)

Calculates betweenness scores for the individual nodes in a graph

Centralization is a graph-level score created by comparing the centrality values (betweenness, degree, eigenvector etc.) of the nodes in a graph against the node with the highest centrality. A "star" graph has a centralization of 1, whereas a "full" graph (everyone is connected to everyone) has a centralization of 0.

In general it identifies the influence of the most central nodes on the entire graph.

Parameters

graph	- the graph for which to record the scores.
attr	- the graph attribute for which the centralization score is based on.