What is Google map's spatial reference system using when you enter a lat, long into the maps search bar? I've found hints that it might be WGS84 but after converting to that coordinate system, not...

I've based my query below to select points near a spatial point called point on the other SO solution, but I've not been able to get it to return any results, for the past few hours, and I'm a bit ...

This is a basic question but unfortunately I could not find the relevant command elsewhere. Is there a way i can convert a Spatial Points Dataframe to an ordinary dataframe in R. e.g. if the ordi...

Imagines there's a 2D space and in this space there are circles that grow at different constant rates. What's an efficient data structure for storing theses circles, such that I can query "Which ci...

Hello I have a network in R using the igraph library Vertices: 616 Edges: 6270 Directed: TRUE No graph attributes. Vertex attributes: name, Lat, Lon. Edge attributes: V3. How can I generate ...

I have multipolygon that looks like a star with an empty hole in a middle: image How do I transform this multipolygon into a single polygon or multipolygon that also includes the hole in a middle,...

I'm using Python in an attempt to analyse a large chunk of empiric measurements. In essence, I've two functions transforming the empiric data which also takes 3 'count' parameters - and retur...

So I have a spatialpolygons object in R; but I am not sure why I am unable to retrieve the "area" slot from it. Here's my R session: > spatialpolygons An object of class "SpatialPolygons" Slot...

How can I query the postgres Point type from clojureql? I wish to use the PostGIS functionality but clojureql does not seem to include this.

I need to use an existing PostGIS database from my Rails application. So far I am able to access the DB just fine, GeoRuby nicely converts the 'geom' column into a Point object. What I am looking ...

In my 2D game, I have static and dynamic objects. There can be multiple cameras. My problem: Determine objects that intersect with the current camera's view rectangle. Currently, I simply iterate ...

I have 2 tables one with points as geographies and other with polygons as geographies. I am able to find which polygon a single point falls(from the point table) by the following query: DECLARE @p...

I am trying to calculate distance between two locations using spatial functions in both Mysql and PostgresSQL. I have taken the latitude and longitude from Google. The details are below Location o...

I have about 75 million records in a SQL Server 2008 R2 Express database. Each is a lat long corresponding to some value. The table has geography column. I am trying to find one nearest neighbor fo...

I'm seeing some strange performance issues on SQL Server 2008 with a nullable geography column with a spatial index. Each null value is stored as a root node within the spatial index. E.g. A table...

I am trying to work out the most efficient query to get points within a radius of a given point. The results do not have to be very accurate so I would favor speed over accuracy. We have tried usi...

I am fairly new to R, but not to ArcView. I am plotting some two-mode data, and want to convert the plot to a shapefile. Specifically, I would like to convert the vertices and the edges, if possibl...

I am interested in good literature about spatial indexes. Which one are in use, comparisons between them in speed, space requirements, spatial queries performance when using them etc.

I'm trying to draw a google maps that has multiple Circle overlays, however I do not want to reveal the correct center of the radius. So for example, myLatlng is my lat/lon center of the radius, I...

Update: Link to my test dataset I have some data like this: 10.0 11.0 0.5 10.0 12.0 0.5 10.0 14.5 0.5 10.0 16.0 0.5 10.0 18.5 0.5 10.0 19.0 0.5 10.0 19.5 0.5 10.0 20.0 0.5 Using Gnuplot, I co...

I have a database with a field for spatial data and a cakephp interface for it. In MySQL I can save the data by doing: INSERT INTO nodes (Location) VALUES (GeomFromText('POINT(42.450071 -76.487664...

SpatialKey generates some really nice looking heatmaps, and we're looking into what's involved in doing this for an internal project to visualize large amounts of points. I'm looking for feedback o...

Hi have some question regarding spatial and temporal locality. I have read in the course theory that spatial locality If one item is referenced, the likelihood of other address close by will be r...

Does anyone know (ideally, with a reference), whether the VS2010 release of LinqToSQL or EntityFramework v4 will support queries over the SQL 2008 spatial data types?

I'm looking for ways to programmatically convert my GPS logs to images and would like to do this in Ruby... if that's an acceptable tool. I have no GIS background whatsoever but as a programmer i t...