Questions tagged [routing]

consist of finding optimal paths along geographic networks such as roads or trail systems.

577 questions
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How to convert a track of points into walking directions?

Imagine you have a list of points (latitude + longitude) you have previously recorded with a GPS receiver. Now, you need to convert it to a textual representation of the route you followed. Example: Start at Redmond Avenue 12 Walk 200 m Turn left…
Guido
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methods for solving this simple routing problem

In my transport geography class, we were asked to do a "best guess" on the route which does the following on this graph: Starts at A Visits each node Returns to A minimizes distance. I wrote up program which calculated all of the five step paths…
canisrufus
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Google Maps City Crawler

This question is just theoretical but it occurs to me that it can't be all that impossible. Seeing as how Google is just a big web spider that essentially starts out at one page, like index everything starting at such and such a page dealing with…
Steven
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how to determine drive times like those available in google maps

I'm very new to GIS but have played around a bit with PostGIS and QGIS. I'm wondering if there's a way to generate drive time estimates like those given by google maps using open-source tools. For a small number of routes, I can query google maps,…
gisnovice
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1 answer

How to build a web site or mobile app with a circular routing capability?

Hoping this is an easy one... I want to build a web/mobile app for a college project which allows the user to enter a start point and a distance to travel e.g. distance to travel = 6km and the site would then plot a 6km circular route which brings…
Aimee_MFT
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Open Source Tools for Swept-Path Analysis?

Before I spend time writing something, does anybody know of any open source tools to perform swept-path analysis (preferably suitable to run on Windows and a Python API would be a bonus)? I pretty sure I can figure it out, but I'd rather not…
MappaGnosis
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How do GPS receivers map out directions?

Although I've never really dug into it, I've always assumed mapping out directions in a GPS unit is done with A* or Fibonacci-heaps at a higher level and Dijkstra's algorithm for smaller graphs. Are there any other algorithms being used that aren't…
Jon Bringhurst
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stall-on-demand for contraction hierarchy routing: explanation with sample code sought

I've implemented a contraction-hierarchy routing system, which now works well, and I now need to add the stall-on-demand technique to speed it up; as explained here it can reduce the search space dramatically: over 25-fold in the example…
Graham Asher
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Connecting two points with existing polylines

I have two layers, one with the points I want to connect and one with the existing streets. Now I want to find a route along those polylines to connect my two points. I didn't find any tools yet. How can I do this? I'm using QGIS 3.0 If it is…
Alisia
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