Junction
A Junction is a point at which two or more edges meet in a topologically correct dataset. [1]. Junction rules explain how the points and edges interact. Junctions are necessary for network analysis in a network dataset and a geometric network. Junction rules explain what things can occur at the junction point and are related to topology. They behave differently in each type of network.
Junctions and Network dataset
Junctions are needed for network analysis. In a network dataset junctions can be coded with information about the types of turns or stops that are allowed at that point. [2] Some examples of information for a road network that a junction can contain are:
- one-way complete stop
- four-way complete stop
- dead ends
- right turn only
- U-turn allowed
- yield
Junctions and Geometric network
Geometric networks only allow movement in one direction. Junctions in these types of networks are usually source points, edge intersections or valves. [3] A source point junction is where the movement starts. In a water utility geometric network the source point would be the origin of the water.
References
- ↑ GIS Dictionary: Junction. ESRI.
- ↑ Jensen, John R.; Jensen, Ryan R. (2013). Introductory Geographic Information Systems. Boston: Pearson. 202.
- ↑ Jensen, John R.; Jensen, Ryan R. (2013). Introductory Geographic Information Systems. Boston: Pearson. 222.
