Network Types and Interface

Networks in Erdos.jl are graphs with additional ability to store properties associated to vertices, edges and the graph itself. The ready to go network types are the Network and DiNetwork types. Custom types con be defined inheriting from ANetwork and ADiNetwork abstract types.

Abstract Types

# Erdos.ANetwork — Type.

abstract type ANetwork <: AGraph end

An abstract graph with the additional possibility to attach properties to vertices and edges.

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# Erdos.ADiNetwork — Type.

abstract type ADiNetwork <: ADiGraph end

An abstract directed graph with the additional possibility to attach properties to vertices and edges.

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# Erdos.AIndexedEdge — Type.

abstract type AIndexedEdge <: AEdge end

Edge types with unique indexes, accessed by idx

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Network / DiNetwork / IndexedEdge

# Erdos.Network — Type.

mutable struct Network <: ANetwork
    ne::Int
    edge_index_range::Int
    out_edges::Vector{Vector{Pair{Int,Int}}}  #unordered adjlist
    epos::Vector{Pair{Int,Int}}    # position of the edge in out_edges
    free_indexes::Vector{Int}       # indexes of deleted edges to be used up
                                    # for new edges to avoid very large
                                    # indexes, and unnecessary property map
                                    # memory used
    props::PropertyStore
end

A type representing a directed graph with indexed edges.

Network(n=0)

Construct a Network with n vertices and no edges.

Network(adjmx::AbstractMatrix; selfedges=true, upper=false)

Construct a Network from the adjacency matrix adjmx, placing an edge in correspondence to each nonzero element of adjmx. If selfedges=false the diagonal elements of adjmx are ignored. If upper=true only the upper triangular part of adjmx is considered.

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# Erdos.DiNetwork — Type.

mutable struct DiNetwork <: ADiNetwork
    ne::Int
    edge_index_range::Int
    out_edges::Vector{Vector{Pair{Int,Int}}}  #unordered out_adjlist
    in_edges::Vector{Vector{Pair{Int,Int}}}  #unordered in_adjlist

    epos::Vector{Pair{Int,Int}}    # position of the edge in out_edges
                                    # the first in the pair is the vertex
                                    # with lower index

    free_indexes::Vector{Int}       # indexes of deleted edges to be used up
                                    # for new edges to avoid very large
                                    # indexes, and unnecessary property map
                                    # memory use
    props::PropertyStore
end

A type representing an directed graph with indexed edges.

DiNetwork(n=0)

Construct a DiNetwork with n vertices and no edges.

DiNetwork(adjmx::AbstractMatrix; selfedges=true)

Construct a DiNetwork from the adjacency matrix adjmx. If selfedges=false the diagonal elements of adjmx are ignored.

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# Erdos.IndexedEdge — Type.

struct IndexedEdge <: AIndexedEdge
    src::Int
    dst::Int
    idx::Int
end

An indexed edge type

IndexedEdge(u, v) = IndexedEdge(u,v,-1)

Creates an edge with invalid index.

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Defining new network types

In order to define a custom network type, e.g. MyNet <: ANetwork, the corresponding methods in the preceding paragraph have to be implemented. This is automatically done for custom network types having a props::PropertyStore member. Take a look to src/factory/net.jl and src/maps/property_store.jl for an example.