# Tagged Questions

A technique for resampling raster data in which the value of each cell in an output raster is calculated using the value of the nearest cell in an input raster.

1k views

### Nearest Neighbor calculation in PostGIS

I'm learning how to use PostGIS and spatial databases for analysis. What I am trying to do is perform a calculation to get the distance for the nearest polygon in a file, using the edge calculation, ...
6k views

### PostGIS nearest point with ST_Distance

I need to obtain on each element on one table the closest point of another table. The first table contains traffic signs and the second one the Entrance Halls of the town. The thing is that I can't ...
3k views

### Optimizing a nearest neighbor calculation using PostGIS

I'm using PostGIS to calculate the nearest neighbors of polygons. What I want to calculate is the minimum distance from each polygon, to the nearest polygon. Thus far I have got great help from Mike ...
6k views

### How to find nearest neighbors between two tables with point locations in SpatiaLite?

I have started playing with SpatiaLite today and already stumbled upon a problem. For each point location stored in tableOne I would like to select one, nearest (linear distance) point from tableTwo. ...
6k views

### Algorithm to find nearest point

I've a list of a few hundred cities with their latitude/longitude. Given another location (also in lat/long) I need to find the nearest city. As I don't use any GIS, by now the obvious algorithm is ...
2k views

### Find Nearest Line Segments to Point

Background From a known Point, I require to establish the nearest surrounding "visible perimeter" against a table of MultiLineStrings, as shown on the diagram. I've searched this site with a number ...
1k views

### Nearest Neighbor problem in Postgis 2.0 using GIST Index (<-> function)

I'm trying to use Postgis 2.0 new function <-> (Geometry Distance Centroid) in order to calculate, for each row of my table (cosn1), the distance to the nearest polygon of the same class. I was ...
467 views

### nearest neighbor query in SpatiaLite

I am trying to find the nearest line to each point in a layer, and I have over 1 million points. I want to be able to associated the closest unique line ID with the point unique IDs. I have tried to ...
917 views

### PostGIS: Assign ID of point in layer A to closest point in Layer B

This should have been an obvious precursor (that I didn't ask) to my other question: PostGIS function to create spider diagrams? If I do not know the relationship between a point in layer A (stores) ...
11k views

### Find closest lat long to an input lat long (SQL Server 2008)

I have a point cloud in my database (SQL Server 2008 spatial). That is about 6 million records. There are 3 columns: id, value, geom. What is the optimal way of getting the 'value' at input lat long?? ...
823 views

### Distance to nearest point for every point same SpatialPointsDataFrame in R

I have a SpatialPointsDataFrame that I'm working with in R. I want to add a new vector to the dataframe that contains, for every point, the distance to the nearest other point in the ...