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

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4
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1answer
52 views

How to include aggregate field values of clustered points

I am creating a map that has point features representing things like campgrounds, picnic areas, boat launches, etc. In cases where many points are clustered in an area (representing amenities for the ...
0
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0answers
15 views

Aggregating points when overlapping? [on hold]

I know this topic has been already posted many times, but I didn't find satisfying answer. I have some points with the same Geom, but I don't want to spread them, but rather aggregate them in a ...
0
votes
0answers
11 views

Aggregate OD-matrix (ArcGIS)

From a transportation model I have got an OD-matrix. This may for example be cartrips between (to-and-from) different small areas (1-16), see figure below: Is there any way where I can select ...
0
votes
0answers
17 views

Reprojecting and Aggregating a 30m resolution raster to a 3 arcsec raster

I am a using a 30m x 30m resolution land use raster that is projected in NAD83 Québec Lambert but would like to convert it to make it compatible with a 3 arcsecond flow accumulation raster that is ...
0
votes
2answers
54 views

R: creating an error matrix from two rasters

I have two land use rasters (6 classes each) and I'd like to create an error matrix (errors of omission and commission) from them both. The premise is that I have a very fine 'base' raster and have ...
1
vote
1answer
58 views

Aggregate census tract data to county level

I have data on a census tract basis but I am having trouble aggregating them to county level. Is there any tool to do it in ArcGIS?
1
vote
1answer
48 views

Using FME to aggregate POI to one point

I want to aggregate points of interest (POI) using FME. The aggregation should make it possible to group all POI within an area based on a buffer distance from the centerpoint of n POI. This would ...
0
votes
1answer
105 views

Counting raster values using another raster as mask in R?

I would like to count the frequency of values in one raster, using another raster (different resolution) as the zonal condition. The premise is that the coarser resolution raster represents the area ...
0
votes
0answers
15 views

Aggregating Individual District Assignments to Census Block

Working on a solution that may work but figured I'd ask the community to see if there's a smarter way to get this task done. I have a voter registration file with district assignments for each voter. ...
1
vote
2answers
208 views

R: aggregate raster with 'mode' function - how does it work?

I want to aggregate a very fine resolution raster at various coarser resolutions (that represents many 1000s of categorical polygons). The aggregate{raster} function is what i've traditionally used, ...
0
votes
1answer
145 views

When aggregating points by polygons with sp::over function, how do I include attribute data from both the points and polygons? [duplicate]

Data: Zipped ea.ml1 shapefile can be found here, and the country outline can be downloaded here at the GADM site. I've been using the Ethiopia ESRI shapefile. Branch locations are here. I have a ...
4
votes
1answer
56 views

Overlapping line aggregation+trim in PostGIS, while summing values

I'm sorry for the vague title, I didn't really know how to name this. I am working on a project that visualizes and simulates 17th century trade. For this project we also use so called Minard lines to ...
2
votes
0answers
25 views

proportional aggregation of census data between layers in QGIS?

not sure if anyone here remembers the little program called "AtlasGIS"? Well its been discontinued years ago which is a pity, but it had a function where one could proportionally aggregate for example ...
0
votes
0answers
43 views

Geological map generalization polygon aggregation

I am working on generalization of Geological maps and the first thing I am wondering about is aggregation of separate patches that may have same class and which are closely situated to each other. ...
2
votes
1answer
54 views

Strategies for grouping polygons

I'm looking for strategies to replicate the functionality available via ArcGIS' "Aggregate Polygons" tool. This is different from a straight dissolve on the polygons - the operation has to fill in ...
1
vote
2answers
96 views

Aggregate SpatialPoint to form SpatialPolygon

Is it possible to convert SpatialPointDataFrame to SpatialPolygonDataFrame by some kind of generalization or aggregation function in R. how can i form polygons from points of similar color/classified ...
0
votes
0answers
40 views

Aggregate polygons based upon adjacency to an acreage threshold

I work as a forester. I have a feature class of approximately 750 polygons that range in size from a few acres to more than 250 acres. I would like to combine these polygons based upon their proximity ...
1
vote
1answer
114 views

How to aggregate values of different statistical areas that are overlapping?

Let's say I have one polygon layer counties with the polygons of administrative borders and another layer postal codes with the polygons of postal code areas. I have some statistical values per ...
1
vote
0answers
52 views

How can I identify regions with some points as centers? [closed]

I have a Postgres database of entire U.S. zipcodes and their lat/long data. My requirement is to divide these zipcodes into non overlapping regions. All regions have some center zipcode. All ...
0
votes
0answers
51 views

How to bring LSOA data up to MSOA level London using ArcGIS for Desktop?

I need to preform regression analysis but my issue is that I have data at 2 different Output areas, MSOA and LSOA. My question is, how to I bring my LSOA data up to MSOA level?
1
vote
1answer
299 views

QGIS tool for aggregating population data in fishnet

I'm looking for a tool or method to aggregate a vector fishnet based on a minimum value. Specifically, I have a fishnet containing a population value and I would like to join together cells that ...
3
votes
1answer
196 views

GROUP BY on geography in postgres 9.4.0 returns wrong/different results

table definition: CREATE TABLE search ( id bigserial NOT NULL, location geography(Point,4326) NOT NULL, location_aggregated geography(Point,4326) NOT NULL, created timestamp with time zone ...
2
votes
1answer
83 views

Obtaining block structure from parcel data using QGIS or ArcGIS for Desktop?

I am trying to analyze the urban form of a city. I don't have the polygon file for streets, so I must derive block structure from parcel data (see image below). What tool could I use to accomplish ...
0
votes
2answers
96 views

Can you do aggregate functions among nearby geometry in PostGIS?

I want to do aggregation based not on group but on geometry, is that possible in PostGIS? For example to calculate max, min, average price for all listings that's nearby a geometry point, how can I ...
1
vote
0answers
191 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 vehicle)...
2
votes
2answers
161 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 ...
2
votes
2answers
345 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
57 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 ...
5
votes
1answer
297 views

QGIS equivalent to ArcGIS Aggregate Polygons?

I am looking for a tool in QGIS 2.40 that performs the function ArcGIS refers to as Aggregate Polygons. Basically it takes a group of polygons within a specified distance and creates a concave hull ...
3
votes
2answers
156 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
53 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, ...
4
votes
2answers
3k 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
118 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
163 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 ...
1
vote
3answers
385 views

Query to find the Intersection coordinates of multiple Polyon

I am using the below Query to find out the intersection coordinates of 2 Polygon and its working fine,but how to use or modify the query to find the intersection area coordinates for multiple(or N ...
3
votes
2answers
747 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 ...
11
votes
2answers
5k 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 ...
3
votes
2answers
1k 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
323 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
1answer
396 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
548 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
6k 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 ...