To combine data into larger units. For example a group of points to a polygon, or political subdivisions (provinces) to larger entities (country).

learn more… | top users | synonyms

1
vote
0answers
59 views

Simplifying geometries and calculating non-spatial averages

I'm quite new to using proper spatial tools, and have a simple question that doesn't immediately show up on google. I have a table that contains multiple rows of empiric data (say, speed of a ...
1
vote
2answers
34 views

Dissolving adjacent polygons and adding attributes

I am trying to merge together adjacent polygons and have the attributes added together for the merged features. The layer is of certain census blocks across a state (thousands of features) and I ...
1
vote
2answers
86 views

Aggregating satellite night light data in R

I am working in R and having some difficulties with extracting values from a raster layer. What I am trying to do is aggregate satellite night light data from pixel to polygons. However, when I ...
1
vote
1answer
27 views

Why am I getting small float numbers when aggregating points containing large integer values in QGIS?

I have a layer of points containing the centroids of European NUTS regions at NUTS 3, with population data in the atttribute table. I want to aggregate this population data to NUTS level 1, which is ...
0
votes
0answers
66 views

How to aggregate data which meet certain conditions using QGIS?

I have a point shapefile with meteorological stations which contains three columns, which are: Date: The date on which the measurement has take place (it covers a range of ten years) Id: The ...
3
votes
2answers
78 views

Method for automatic aggregation of polys with sparse data

I am part of a project on presenting health related data on maps. In order to maximize the analytical usefulness of the data, we wish to divide them into as small areas as possible. However, to ...
2
votes
1answer
39 views

How to use PostGIS for tile-based aggregation?

How can I create a tile-based aggregation of polygons with PostgreSQL/PostGIS? The input of such an operation could be the database table with the geometry and the data to aggregate, a bounding box, ...
1
vote
2answers
693 views

Dissolve/aggregate polygons with ogr2ogr or gpc?

I have a large number of polygons representing the boundaries of US counties which I need to merge into as few polygons as possible. Is it possible to do this with non-commercial software, or ...
1
vote
0answers
80 views

level of spatial aggregation of polygons

I am looking for a method that allows me to obtain the spatial aggregation of polygons for each cell of a grid with 10kmx10km resolution. In each cell (10kmx10km), I want to be able to consider that ...
1
vote
1answer
97 views

Spatial Aggregation of attributes from line structures in polygons

maybe someone has an idea how to deal with it (or directly knows the equivalent functions in PostGIS) for the following problem: I have a transport network (something like railways) and the ...
3
votes
2answers
379 views

Postgis: aggregate function for intersection

I have a PostGIS Table with LINESTRINGS. I like to a query that returns all Roads that are connected. So I get a set of unconnected trees (in german 'Wald (Graphentheorie)') pseudo code: select ...
10
votes
2answers
2k views

Aggregating points to grid using R

I have a question with regard to spatial aggregation in R. What I am trying to do is aggregate a point dataset to a grid. I am unsure however how to do this as I have little experience with this sort ...
2
votes
2answers
561 views

UK Postcode District Aggregation

I've had a request recently to generate a map which includes UK Postcode districts, ie aggregations of postcodes based on the first section of the code (NW2, B1, E11 etc.). From what I've read, these ...
2
votes
2answers
204 views

how to aggregate raster values for each grid in a fishnet-like map

here is my problem: I have a raster layer containing the elevation info. and another gridded layer (shapefile type). What I want to do is to calculate the mean elevation within each grid to have a ...
3
votes
0answers
225 views

Area-weighted rasterising of polygon data

I'm looking for any GIS tool to do detailed rasterising of polygons. I've checked GDAL's gdal_rasterize command (and API), and ArcGIS's Polygon to Raster tool, but they only rasterise 1 attribute per ...
10
votes
2answers
368 views

Aggregating Polygons To Meet Privacy Requirements

I have a point feature class representing office locations of all employers in a certain industry. The feature class has an attribute for storing the number of employees working at each office. ...
2
votes
3answers
3k views

How to aggregate points to polygons using ArcGIS Desktop?

I am trying to aggregate my data points to the polygons so that I could find out how many points I actually have in each polygon, and then export the data contained within each polygon to further look ...