Node statistics

Node Statistics

RivEX can extract and store various statistics for each node.

To compute the node statistics you must complete the parameters section of the main interface and press build to construct the dictionaries used to analyse the river network.

RivEX Interface

Select the Analyse Network tab, tick the node statistics checkbox and select which nodes you want to process. You can choose to process all nodes or exclude pseudo nodes from the analysis. Start the process by clicking on Go!

RivEX assumes you may have changed the default Strahler field name so you will always be asked to identify the field as shown below.

Strahler order option

This field is generated by RivEX so you must run your river network through RivEX first to create the Strahler field.

Once the process has finished, you will be asked where to direct the output as shown below.

Output option dialog

Select YES sends the output to MS Excel. The Excel application will minimise when data transfer has completed, do not click on the window until this has happened!

Select NO sends the output to a dbase file called LayerName_Node_statistics.dbf stored in C:\RivEX\Output. For example if you processed a river network call riv, RivEX will create a file called riv_Node_statistics.dbf. If this file exists already you will be asked to overwrite it.

The statistics calculated for each node are:

Statistic	Field Name
Node ID	NodeID
Valency	Valency
Node Type	NodeType
Number of inflowing polylines	NumInFlow
Number of outflow polylines	NumOutFlow
Minimum Strahler order	MinStrahlr
Maximum Strahler order	MaxStrahlr

RivEX Logo