Networks




Create graphe

This tool allow the qgis user to create a graphe from a polylines layer. It adds two fields called « i » and « j » in order to write starting and ending node ids.

Node ids are create in texte format. The use of a prefix enables to paste an id with the incremental number automatically genrerated. For example, with the prefix ‘FR’ for France, nodes ids will be labelled FR1, FR2, ...

The tool generates a node layer in the same CRS as the linear layer, which can be loaded automatically if the « Add nodes in active map » is checked




« Create graph » Legend


Invert

This tool will revert the line direction of the previously selected polylines.


Split

This tool will split the previously selected polylignes into simple lines (only two points)


Connect

This tool allow to connect node layer objets to a linear objets layer. Each point will be connected to the nearest polyline, if the shortest distance to the polyline is lower than the serach radius The polyline will be split in two parts from each side of the connection point, in order to preserve the network topology

NB : Multilinestringsare ignored



connect point’ legend