Transportation Geography and Network Science/Topology

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Circuits and Trees[edit]

Circuits and Trees are two basic structures of planar networks. A circuit is a closed path, with no less than three links, that begins and ends at the same node. A tree is a set of connected lines that cannot form a complete circuit. [1]

At the individual trip level, the treeness is estimated as:


\phi_{tree} = \frac{l_{tb}}{l_{sb}}

where:

l_{tb} = Length (km) of street segments belonging to a branch network within the buffer,

l_{sb} = Total length (km) of the street network within the buffer.


References[edit]

  1. Open source software developed by Feng Xie, Metropolitan Washington Council of Governments (MWCOG) can be used to identify tree and circuit links on planar networks. Code can be downloaded from [1]