A* is a graph shortest-path algorithm that uses a heuristic function to speed up the search

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Convert Road layer shapefile into a graph

I'm going to use Astar algorithm to find a path between two selected points.And I used the following code for that.Is there any way I could convert my Road Layer shapefile into a graph, which can be ...
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184 views

Does not show shortest path in networkx (in QGIS)

I used the following commands (in qgis console) to get the shortest path with astar algorithm. But the result shows 'NetworkXNoPath' every time. Why was that? Please help me to find a solution to this ...
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163 views

Development guide for beginner? [duplicate]

Im new to GIS and mapping, and I need to learn how to create web map application for my project. I'm really confused on what to use. I have read PostGIS, OpenStreetMap, and Openlayer. I'm wondering ...
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How to add nodes into graph

I'm new to qgis and in here I want to find a path between two selected points on the map(Roads-vector layer). The points are selected by the user, using mouse clicks. So here I used the astar ...
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'QgsGraph' object does not support indexing

Traceback (most recent call last): File "/home/kasun/.qgis2/python/plugins/floogin/floogin.py", line 246, in findRoutes path=self.astar.astarSearch(graph, start, end) File ...
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Complexity of A-star algorithm using pgRouting in a graph

I'm using the A-star algorithm in pgRouting. It uses the Manhattan distance as a heuristics ((|dx|+|dy|)/2). What would be the time complexity in a standard route network? Based on Why is the ...
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22 views

Is it possible to calculate the route when source and destination having same junction using A* algorithm?

I am using A* Algorithm to calculate the shortest path. The route was calculated based on the junction. Shortest route was calculated when there was two or more junction in between source and ...
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166 views

Python/GDAL: Best way to read in raster for use in A* search algortihm

I want to create a least cost path program with Python and GDAL since I couldn't find any open source cost path additions for use in Python. As recommended here the best approach is to use A* ...
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201 views

How to correctly convert data from OSM with osm2po to use it with A* algorithm?

I want to make my A-Star fast, by using heuristics. At the moment it is very slow and even slower than my Dijkstra. I thougt A-Star is in the worst case as fast as Dijkstra. I convert my OSM bounding ...
2
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152 views

Why is pgrouting astar not consistent?

I route from 1 end of a circular route to the opposite end. Visually it is obvious that going clockwise is shorter, however shortest_path_astar sometimes picks clockwise and sometimes anti-clockwise. ...
3
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Shortest distance from pgrouting with cost not being length: optimal solution

I'm using pgrouting shortest_path_astar with a complicated cost function. It gives back the edges, vertices and costs. I would like to get the total distance of this shortest path (i.e., the sum of ...