Counting an individual loops & total number of loops & identifying the bridge connection

Feb 24, 2011 at 10:47 PM

Hi all,

I am trying to apply NodeXL package in water distribution network and trying to find out the number of indidual loops & total number of loops. In addition to that, I am playing with the groups data which can be formed in NodeXL with which to find out the connectivity, specially a bridge connection with which two clusters are depend on the bridge either side. My main focus is to find out the bridge in the large network. Further to measure the connectvity of the network after failure the bridge (link/edge).

For example:

1) The individual loop means in a single network

     If triangle A-B-C formed a loop by joining all the 3 vertices by 3 edges. Simillar like a square A-B-C-D with 4 vertices & edges

2) The total number of loops means in a single network

The loops wich can be formed by all the possible way including individual loops (might be possible from some edges from the triangle & some edges from the square or any other shape which can be overlaped with lots of combiantions) . Here, I do not mean the loop i.e. edge is connected to a single vertices itself.

How can I explore these two issues with NodeXL:  1) The number of loops &

                                                                         2) The bridge connection

 

With Regards

Santosh

MSc Students

UNESCO-IHE (Institute of Water Education)

Delft, The Netherlands

schobhe@gmail.com

chobh1@unesco-ihe.org

 

Feb 25, 2011 at 6:02 AM

Santosh:

NodeXL doesn't have anything that will do something that specific.  It will calculate a number of popular graph metrics, such as degree, various centralities, PageRank, and so on, but what you are describing sounds like it would take some custom programming to get the job done.  If you are a .NET programmer, you could use the NodeXL Class Libraries (available under Other Downloads at http://nodexl.codeplex.com/releases) to write a custom IGraphMetricCalculator implementation that analyzes your loops and bridges; or if you are a VBA programmer, you could conceivably add VBA code to your NodeXL workbook to do the calculations.  But NodeXL won't do what you want on its own.

-- Tony