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.. index::
   single: Metrics Family ; pgr_bandwidth - Experimental
   single: bandwidth - Experimental on v4.0

pgr_bandwidth - Experimental

pgr_bandwidth - Calculates the bandwidth of the graph

Availability

.. rubic:: Version 4.0.0
  • New experimental function.

Description

Bandwidth measures how "spread out" the connections are in a graph when vertices are arranged in a linear order (like numbering them 1, 2, 3, etc.).

  • For each edge in the graph, calculate the distance between the vertex numbers it connects
  • The bandwidth is the maximum of all these distances
  • The implementation is for undirected graphs
  • Run time is 0.160789 seconds

|Boost| Boost Graph Inside

Signatures

Summary

pgr_bandwidth(Edges SQL)

Returns BIGINT
Example:For an undirected graph with edges. 
.. literalinclude:: bandwidth.queries
   :start-after: -- q1
   :end-before: -- q2

Parameters

Inner Queries

Edges SQL

Result columns

Returns a bigint (pgr_bandwidth)

Column Type Description
pgr_bandwidth BIGINT gives the bandwidth of the graph.

Additional Examples

Example:Undirected graph with edges before optimization. 
.. graphviz::

   graph G {
    node [shape=circle, style=filled, fillcolor=white, color=black, fontcolor=black, fontsize=10];
    edge [color=black, penwidth=1];

    4 -- 7;
    7 -- 9;
    7 -- 0;
    0 -- 2;
    2 -- 5;
    5 -- 9;
    9 -- 8;
    9 -- 1;
    5 -- 1;
    9 -- 6;
    6 -- 3;
    1 -- 3;

    {rank=same; 4; 8; 6;}
    {rank=same; 7; 9; 3;}
    {rank=same; 0; 2; 5; 1;}
  }


.. literalinclude:: bandwidth.queries
   :start-after: -- q2
   :end-before: -- q5
Example:Undirected graph with edges after optimization. 
.. graphviz::

   graph G {
    node [shape=circle, style=filled, fillcolor=white, color=black, fontcolor=black, fontsize=12];
    edge [color=black, penwidth=1];

    0 -- 1;
    1 -- 3;
    1 -- 2;
    2 -- 4;
    4 -- 8;
    8 -- 3;
    3 -- 5;
    3 -- 6;
    3 -- 7;
    8 -- 7;
    6 -- 9;
    7 -- 9;

    {rank=same; 0; 5; 6;}
    {rank=same; 1; 3; 9;}
    {rank=same; 2; 4; 8; 7;}

  }


.. literalinclude:: bandwidth.queries
   :start-after: -- q5
   :end-before: -- q8

See Also

Indices and tables