A graph is a representation of a set of objects where some pairs of the objects are connected by link

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8
votes
0answers
172 views

Can GRASS compute the line graph representation of an input graph?

I'm interested in computing a line graph for an input graph, preferably in GRASS since I'll be using other GRASS network analysis tools afterwards. I couldn't find any reference to line graphs in the ...
7
votes
1answer
3k views

What are the existing datasets of world maritime routes?

I have a list of cargo ports of all over the world and need to show some port-to-port trips on a map, and also to compute lengths of these trips. For that, I need a dataset of actual maritime routes ...
6
votes
2answers
399 views

How can I turn a vector layer into a graph G = (V, E)?

I have a number of rail networks, in the form of shapefiles of the "line" type. I want to turn them into a more abstract graph format, i.e. the kind with vertices and edges, not chart-type graphs. ...
6
votes
3answers
2k views

Find a proper path between two nodes in a grid

This question is about finding a proper path (route) between two nodes (P,Q) in a grid (i.e., graph, network, ...). In our concept, we define a path proper (nice) if it is the most similar* to the ...
6
votes
1answer
398 views

Accessing graph in ArcMap document using ArcPy?

I am trying to access an existing graph in an ArcMap document with arcpy. I know how to create a new graph with arcpy, but I cannot seem to figure out how to access an existing graph in an ArcMap ...
6
votes
1answer
267 views

How to filter the graph on which I want to find the shortest path

I have a large graph that contains edges of Europe. I want to calculate the shortest path between two points on this graph with pgRouting that have a function pgr_trsp for shortest path calculations. ...
5
votes
5answers
820 views

What software would be useful to create General Transit Feed Specification (GTFS)?

I am doing a project in which i am required to create GTFS. I look at transit google developer forum which provide a format to create feed but that completely have to done by hand (we have to write ...
4
votes
4answers
258 views

Creating best fit line from point data using ArcGIS for Desktop?

I have GPS points that show the locations of surface bubbles from a research dive along a transect. Wind, waves, and currents have conspired to add error to these data. I want to create a single best ...
4
votes
1answer
44 views

Access to graph properties in arcpy

I am using data driven pages and arcpy.Graph() object to automate production of synchronised map/long-section series similar to this: I'd like to keep vertical scale for long-section part. In order ...
4
votes
1answer
838 views

Problem: Arcpy Graph function empty graph output

Background: I have some python code that I need help with parameter passing into the MakeGraph_management arcpy function. I would like to create a two-series vertical line graph for every pair of ...
4
votes
2answers
158 views

QGIS create a line graph with attributes value on a section through the map

I wonder if I can make cross sections of GIS data (other than height). An example: I have a shapefile of a city with building plots and attribute values of the plot size. I want to choose a random ...
4
votes
1answer
1k views

Elevation graph from GPX file

I've got many GPX files in the following format: <?xml version="1.0" encoding="utf-8"?> <gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" ...
3
votes
2answers
1k views

How to rotate external graphic using mouse in Openlayers?

I would like to rotate externalGraphic using mouse something like this URL. In this URL polygon is used to rotate it but I want an image to be rotated using external graphics tag. Any help is ...
3
votes
1answer
823 views

How to create a x-y scatterplot from attributes in QGIS 2.0?

There are a few old packages that allow the creation of x-y scatter plots from attributes in vector data (Scattergram for 1.7) http://plugins.qgis.org/plugins/scattergrammidentify/ (SPQR for very ...
3
votes
1answer
407 views

Bar graph - cartodiagram in QGIS

Can I create a cartodiagram in QGIS 1.7.3? I need one bar graph in every territorial unit of one layer. It must vizualize organization on X and number of research in one organisation. Is it possible? ...
3
votes
3answers
718 views

Visualization of a big graph in 3D from postgresql/postgis

We have a graph in 3D in a PostgreSQL/PostGIS database. It contains something like 50'000 edges and 50'000 vertices, with x-y coordinates and floors. We would like to visualize this graph with ...
3
votes
0answers
376 views

Make Graph (Data Management), Changing item names in legend [closed]

I'm having python produce a multi-series graph. How do you change the series name in the legend, the default being Vertical Bar, Vertical Bar1, Vertical Bar2.... ...
2
votes
2answers
347 views

Why is arcpy.StackProfile_3d -> arcpy.SaveGraph_management creating empty graph?

In a python script I'm trying to save a graph to a .png file with graph output from arcpy.StackProfile_3d but the .png file shows an empty graph. The table created from arcpy.StackProfile_3d shows ...
2
votes
1answer
130 views

Converting Historical Railroad Systems Data from KML?

I'm writing a paper for an undergraduate economic history class and I'm interested in North American railways in the 1800's. I've found historical GIS data for the period here. The railroad data are ...
2
votes
1answer
229 views

arcgis graph vs .net graph

I am trying to show some elevation/cross section data in a graph. I am trying to do this in arcgis graphs. But because of my previous graph work was in .net, I found arcobjects.net API for graphing is ...
2
votes
1answer
371 views

Using histogram in ArcGIS 10 with dates and sum of values

I have a point feature layer in ArcGIS. I want to add a histogram which shows a histogram for selected points. This works perfectly. Two problems: I have a datefield, which spans about three years. ...
2
votes
0answers
38 views

Create network graph from contiguous polygons in KML, or PostGIS?

I am using Postgres 9.5 and PostGIS. I have a table with a geometry field. This table has about 200 rows, in each of which the geometry field contains a Polygon. I would now like to derive an ...
2
votes
1answer
73 views

OSM Reverse Geocoding - Find closest node for Coordinates

currently I am experimenting with Neo4j as Database for OSM Data. In the end I'd like to do routing stuff. I had a look at the Neo4j/spatial, but this is to blown up for me (not optimized for ...
2
votes
2answers
72 views

Formula for charting a course around the globe, given a location and degree heading?

I'm looking for a formula that takes a long/lat coordinate and a degree heading, (e.g. "I'm standing in San Francisco and I'm facing 45º from north"), and which can draw a line across a map projecting ...
2
votes
0answers
144 views

How to extract polygons from a road network?

I need to extract faces (or polygons) from my road network and calculate their areas. I mainly use Arcpy packages but even if you know it in QGIS APIs, I'd appreciate if you'd share it with me. If it ...
2
votes
0answers
211 views

ArcPy Add Graph Window

The arcpy MakeGraph_management tool suggests that a graph is stored via an in_memory representation that can be either: added to the host app or saved using SaveGraph_management. The graph appears ...
2
votes
0answers
112 views

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 ...
2
votes
0answers
78 views

Generating Tiles for Non Geographic Datasets [closed]

Excuse my ignorance if this exists. I don't think I've seen a website ever using something like this. Have tools been developed that use general tiling methodology to implement non-geographical data ...
2
votes
0answers
75 views

What graph traversal algorithm should I use?

I would like to write an algorithm which can traverse a graph and hopefully later I can implement it to use for an indoor navigation system. The graph would come from floor plans of a building and the ...
2
votes
0answers
178 views

Plot the Shortest Paths in a Grid without any clash at a point of time

The efficient algorithm needs to be done and proved for the best solution for the given problem: User inputs: (#) Size of the NxN Grid. (N); (#) No. of Paths: Z; (#) Source and Destination ...
2
votes
0answers
425 views

On using R data with ArcPy to make histogram in ArcMap

I am writing a tool in python which passes parameters to a R script, which in turn creates a DBF file. I read this DBF and want to make a histogram out of the data inside ArcMap as one of the results ...
1
vote
1answer
581 views

How to create graph out of two layers using ArcGIS 10.1 for Desktop?

I would like to create a graph of two layers I have. on one hand its the land price of a certain area and on the other a layer with a crime rate. first of all, the layer with the land prices doesnt ...
1
vote
1answer
893 views

Can't select layer in the Road Graph plugin QGIS

I'm trying to use the Road Graph plugin in QGIS 2.2.0. I have tried a few line shape files, but it won't let me select the layer (the option is greyed out). I've tried adding a 'SPEED' field and a ...
1
vote
2answers
341 views

Can I plot this “diagram” in matplotlib [closed]

I am not sure weather that is the right stackexchange here. I want to grade a diagram like this: http://matplotlib.org/examples/shapes_and_collections/scatter_demo.html Unfortunately, I have no idea ...
1
vote
1answer
460 views

How to create pop-ups with graphs on point layers?

i have a postgresql database which is refreshed all 10 minutes and i need to create graphs in pop-up with the data. When i click, a pop-up (or annotation ?) appears. How can i make it possible ? ...
1
vote
1answer
231 views

Display mouse position from graph on a map

i need to develop a web application which shows a map, that displays a GPS Route. So far I can do this using Openlayers or ArcGIS Server. Now I want to add an interactive graph below the map. In this ...
1
vote
1answer
540 views

Data Driven Pages, Graphs, and selections in ArcMap 10.1

Is it possible in python to create a selection set based on the extent from a Data Driven Page (DDP)? I have a layout view with a map and a graph. The graph is set to only plot the selected set of ...
1
vote
1answer
39 views

How can I create a pie chart of species recorded so that the colours match the symbology of the GPS points displayed in my map?

I have created a map in ArcMap 10.3 showing the locations of bat sightings in a borough in London, the symbology set to show the different bat species recorded. I want to have a pie chart as an insert ...
1
vote
1answer
67 views

Create common vertex where line was snapped to another using “snap to segment”

I have a schematic diagram within QGIS consisting of a single layer of line segments. Lines have been snapped to others using "snap to segment". When using the snap to segment option the two lines ...
1
vote
1answer
168 views

Why doesn't QGIS 2.8.2 Road Graph accept my road network vector?

I'm using the Finnish official Department of Transport's "digiroad" road network vector file, which has all kinds of roads, cycle paths etc on it, but I can't use Road Graph on it. If I create a new ...
1
vote
1answer
1k views

How to build a Spatialite road network from OSM data

I'm looking for algorithm which could help me with building my own road network (for routing) from OSM data. I chose Spatialite DB for this, but here I have only one problem: Spatialite provides ...
1
vote
1answer
48 views

What each stack element does

I'm using the opengeo stack, and want to double check my understanding of each element. PostGIS - The database for storing my data GeoServer - The link between the online part / the database ...
1
vote
0answers
17 views

Qgis network prepare road graph

I have been working on finding shortest path between two buildings. For that purpose i have created kml files of various streets, converted them into shape files and then merged all of them together. ...
1
vote
1answer
45 views

Graph preview in Python toolbox

I need to create a toolbox in python, which will be used for making graphs. I need the parallel preview window during the graph creation. Half of the screen will be used for settings the parameters ...
1
vote
1answer
91 views

OSM2PO Postgres to graph for A*

I have created a directed graph from the nodes stored within my Postgres db but the resulting graph doesn't seem to be fully connected and as a result my shortest path algorithm is not able to find a ...
1
vote
0answers
55 views

Create profile graph over multiple rasters (ArcGIS 3D Analyst)

When having a raster which represents an array of values, for instance, elevation, I can generate a profile graph over a line I draw using the 3D Analyst toolbar. A sample graph: When generating a ...
1
vote
1answer
44 views

Extracting coordinates of a triangulation from DEM data

I'm working on the succinct representation of planar graphs and now I'm trying to obtain some datasets to test my results. I saw that Delaunay triangulations of elevation data can be a good source of ...
1
vote
1answer
76 views

Dynamic Profile Graph for Data Driven Page Atlas

I used Strip Map Index Features tool to create a Data Driven Page set of maps and I would need to create a new data frame that will contain a dynamic profile graph that will be modify depending on ...
1
vote
0answers
68 views

Why is the Spatial Analyst toolbar graph different to Graphs>Create Graph?

I'm using ArcGIS 10.3 and want to look at elevation vs frequency of each elevation for a DEM. There seems to be two ways to create this graph: Use the "Create histogram" tool on the Spatial Analyst ...
1
vote
0answers
33 views

An algorithm that could find a random cycle in a graph

I am looking for an algorithm that could find a random cycle in a graph from a node while that cycle is traversing around another nodes (area). For example, from the green star on the left of the ...