Editing Transport network analysis (section)

==History==
The applicability of [[graph theory]] to geographic phenomena was recognized at an early date. Many of the early problems and theories undertaken by graph theorists were inspired by geographic situations, such as the [[Seven Bridges of Königsberg]] problem, which was one of the original foundations of graph theory when it was solved by [[Leonhard Euler]] in 1736.<ref>Euler, Leonhard (1736). "Solutio problematis ad geometriam situs pertinentis". ''Comment. Acad. Sci. U. Petrop'' 8, 128–40.</ref>

In the 1970s, the connection was reestablished by the early developers of [[geographic information system]]s, who employed it in the topological data structures of polygons (which is not of relevance here), and the analysis of transport networks. Early works, such as Tinkler (1977), focused mainly on simple schematic networks, likely due to the lack of significant volumes of linear data and the computational complexity of many of the algorithms.<ref>{{cite journal |last1=Tinkler |first1=K.J. |title=An Introduction to Graph Theoretical Methods in Geography |journal=CATMOG |date=1977 |issue=14 |url=https://alexsingleton.files.wordpress.com/2014/09/14-graph-theoretical-methods-in-geography.pdf}}</ref> The full implementation of network analysis algorithms in GIS software did not appear until the 1990s,<ref>Ahuja R K, Magnanti T L, Orlin J B (1993) ''Network flows: Theory, algorithms and applications''. Prentice Hall, Englewood Cliffs, NJ, USA</ref><ref>Daskin M S (1995) ''Network and discrete location — models, algorithms and applications''. Wiley, NJ, USA</ref> but rather advanced tools are generally available today.