Partitioning data points into subsets of objects according to their mutual "similarity," without using preexisting knowledge such as class labels.

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1
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1answer
29 views

Visualize large amount of geopoints with Geoserver and PostGIS

I have a postgis database with over 50 million rows. Every row consists of a POINT corresponding to lon,lat and a value (number 1-100) I'm trying to create tiles for zoom levels 5-20 that I want to ...
1
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1answer
29 views

Leaflet - GPX - Clustering

I'm using Leaflet maps together with "Plugins by Pavel Shramov", which allows google usage and GPX file use. This bit was easy enough, but trying now to use markerClusterer. I've spent a few hours ...
1
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1answer
18 views

Changing size of cluster based on number of markers in Leaflet clustermarker

I'm currently using Leaflet's markercluster add-on, which is working really nicely for some of my initial maps. However, I'm wondering if there is a way to modify the clusters so that the size of the ...
0
votes
0answers
12 views

Would like map to be divided by region and for it to cluster markers, based on zoom level, using Google Maps Engine?

I am more of an GIS analyst than a developer and I do not have any Java / HTML coding experience. I was hoping that I could get through this using the Google Maps Engine documentation but it has ...
4
votes
3answers
2k views

Creating collection of polygons from collection of points?

I have a set of points, which are spread over a wide geographical area. I need to be able to create a set of polygons which best represent the clustered points. In parts, some points may simply lie ...
3
votes
0answers
14 views

How to set m parameter of clusterR function in R?

I want to manage a clustered computation on raster and thus use the "clusterR" function in R (package 'raster'). However, there's a tuning m parameter to set, but the only explanation about this ...
0
votes
1answer
26 views

SAGA Cluster Analysis for grids projection issue

I am having an issue with the SAGA cluster analysis for grids tool within QGIS 2.4. I am actually taking this as an online class through Del Mar and we are going over supervised and unsupervised ...
11
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4answers
1k views

How can I generate irregular grid containing minimum n points?

Given a large (~ 1 million) sample of unevenly distributed points - is it possible to generate irregular grid (in size, but could also be irregular in shape if that is possible?) that will contain ...
4
votes
2answers
394 views

clustering points in postgresql to create contour map

UPDATE: To try to make this a little more simple, is it possible to create a query which selects a group of points such that each point in the group is at most X units away from at least one other ...
4
votes
0answers
25 views

Clusters of Same Size?

I am attempting to use the Grouping Analysis tool in the Spatial Statistics (in ArcGIS 10.2) to group state high schools (points) together based on enrollment and location. Is there a way to make ...
3
votes
1answer
119 views

How to create a cluster of crashes?

I have a shapefile with 52K points of road accidents, between 2007 and 2012. Each accident has a severity index. I want show clusters of 5 accidents (at least), for each year, that have a severity ...
23
votes
7answers
1k views

What tools for regionalization/redistricting can you recommend?

I am looking for tools for regionalization / districting in GIS. So far I have been able to identify Districting ArcGIS extension (now also online) REDCAP (currently limited to 50k input polygons) ...
8
votes
1answer
1k views

Grouping map points into fixed cluster sizes?

I have a dataset of 655 lat/long pairs which I'd like to split into about 100 groups. A group should have 5-10 pairs which are geographically close to each other. Dense groups should have more ...
1
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0answers
20 views

Grouping map points into fixed cluster sizes? [duplicate]

"I have a dataset of 655 lat/long pairs which I'd like to split into about 100 groups. A group should have 5-10 pairs which are geographically close to each other. Dense groups should have more ...
1
vote
1answer
33 views

Leaflet/MarkerCluster plugin - how do update the HTML content of a DivIcon?

In Leaflet, I am using the markercluster plugin, in which you can use the DivIcon class to display custom icons for the clusters. You can set your own HTML for these clusters. However, I can't find ...
18
votes
5answers
3k views

How to create a polyline-based “heatmap” from GPS tracks?

This winter I am planning to track my downhill skiing/snowboarding using a GPS. Most of my riding will occur at the same resort. I would like to be able to create a sort of "heatmap" that shows the ...
1
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0answers
17 views

Creating single feature to represent group of individual features, based on location and #, using ArcGIS Desktop?

I am looking for an algorithmic way of handling this situation, as I can do it manually with the ruler and some time, but it would be nice to find a programmatic to have Arc do the work for me, so any ...
3
votes
1answer
67 views

How to find mean coordinates of a cluster of points from a point layer in QGIS?

I have a set of coordinate points. The points are distributed in such a way that some points are clustered around a specific area. There is an option to find out mean coordinates(s) of the whole point ...
9
votes
4answers
442 views

How do I figure out if there are clusters of one set of points around another set of points from a different layer?

I want to see if there is clustering of a certain type of buildings (x) around another type of buildings (y). The two point files are in different layers. I cannot figure out which tool I would use to ...
11
votes
1answer
125 views

Identify points in a shapefile that have no other point within x km with QGIS

This is probably a naive question but I am struggling as a new user to QGIS. I have a very large shapefile (275,000 points, but can break this into about 10 subregions if necessary for faster ...
-3
votes
1answer
78 views

CartoDB Point Clustering?

I need to create clusters in Cartodb. I reffered to this code https://gist.github.com/andrewxhill/8695353. I am still getting an error. <!DOCTYPE html> <html lang="en"> <head> ...
1
vote
1answer
134 views

Get a single cluster from cloud of points with specified maximum diameter in postgis

I have on the order of 2M Geometry Collections with N (median: 2, stddev: 6.6, 75th: 6, 95th: 21) Point objects (repeated points allowed and important) in a PostGIS table. I want to identify clusters ...
42
votes
4answers
12k views

Spatial clustering with PostGIS

I'm looking for spatial clustering algorithm for using it within PostGIS-enabled database for point features. I'm going to write plpgsql function that takes distance between points within the same ...
1
vote
0answers
41 views

Clustering the WGS84 point features (projection transformation aspects)

My question is quite trivial and was discussed many times before (like here) but in our case it has the confounding extra requirements... The list of sparsely distributed 2d point features is stored ...
0
votes
0answers
27 views

Clustering on Geoserver layer appearing out of the map

We are using Geoserver and openlayers to display maps. Geosever layer provides list of sites, since there were many we did a clsutering using Styles. But the problem is when we zoom out completely ...
5
votes
1answer
167 views

How to grow several concave hulls until they completely fill a larger area without overlap?

This is my problem: I have a very large point layer with polling station locations across one country; each point belongs to a specific constituency (900k points, 4k constituencies). I wish to use ...
1
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0answers
48 views

Finding areas with high POINT density from PostGIS table using Python

I have a PostGIS table with thousands of POINT objects and I want to find areas that have a high density of points. I have the DBSCAN clustering algorithm implemented in Python which does exactly ...
5
votes
0answers
365 views

Grouping analysis of points to divide a polygon into n number of sub-regions

I'm attempting to create n sub-regions from a polygon based on a cluster analysis of a bunch of overlapping raster layers (physical layers, eg: depth, currents, waves). Briefly, I can create a ...
1
vote
1answer
348 views

How to use Leaflet Marker Cluster on markers from Leaflet-layerJSON (Overpass API)

I'm having troubles getting the Leaflet Marker Cluster working with Leaflet-layerJSON. I'm trying to make a Leaflet map with data from OpenStreetMap. The markers are showing on the map, but they are ...
2
votes
1answer
50 views

Clusters of points: Determining the centroid (QGIS)

I've basically got the same issue as this post, but can't find a way to transplant the ArcGIS solution to QGIS. I have household-level geo data for 10 villages spread out across the country. I need ...
0
votes
1answer
58 views

Cluster numbering in openlayers

I am using openlayers 2 for making clustering on vector point data for which I am a beginner. I have installed geoserver locally via opengeo suite and using 'world_cities' dataset as an example. I ...
2
votes
1answer
121 views

leaflet marker-cluster JSONP geoserver

I hope I can get same help from here. I started to put together a leaflet map, please see here: http://gis.xyz/leaflet2.html I want to show my postgis point (uk based) features on this map with ...
0
votes
1answer
40 views

Error when running cluster and outlier analysis

I am attempting to run Cluster and Outlier Analysis on a Shapefile Feature Class. The geometry type is a line feature class. I am receiving the following error when attempting to utilize this tool: ...
7
votes
3answers
233 views

How to compare spatial patterns (crime cases vs population)?

I am looking for a way to statistically compare two spatial patterns in shape polygon data (not point pattern analysis). Let's say I have a city map divided in neighborhoods (barrios), in shape ...
3
votes
1answer
472 views

How to cluster Raster data

I have thousands of Raster data concerning the ice coverage at the pole at different times (days) over several years. Now I would like to perform a cluster analysis. I want to split the data into ...
1
vote
0answers
50 views

Monte Carlo test of Space-Time clustering in R

I have several point patterns representing the distribution of territories of a bird species. Each point pattern represents the distribution of one year. I already succeeded in computing Ripley's L ...
1
vote
1answer
119 views

How to disperse clusters of proportional markers or polygons?

I am mapping a set of points in ArcMap that are symbolized using proportional marker symbols based on a numeric field value. The scale of the map has lead to alot of the point markers overlapping. ...
6
votes
1answer
157 views

How to get the centroid of a set of points in POSTGIS?

I use PostgreSQL with POSTGIS extension. I have a set of points in the_geom column from a table myshema.myobjects I would want create a select statement to get the centroid of this cluster, so from a ...
0
votes
1answer
81 views

40k+ points from Shapefile, clustering them and populating on Google Maps/Webapp

I just started a new Python/Django webapp job related to GIS (and i'm totally new to GIS). Here is my task and what i have found so far, and i am stuck as to finding out what's the best way or the ...
3
votes
0answers
29 views

Algorithm for estimating position of many objects and differentiating those?

Let's assume a crowd-sourced tree location use case where a research team asks hikers to GPS the location of a specific tree type in case they encounter it. This will lead to a large number of ...
0
votes
0answers
75 views

Creating a polygon around features

I want to create a polygon around a number of points so that all the points occur within the polygon. The purpose is to do this to a number of different features and see where they overlap.
2
votes
1answer
88 views

Do daytime Road Traffic Accidents (RTAs) have same spatial pattern as those of night?

With the following set of recorded data: Location of Road Traffic Accident (RTA) along 160km Expressway Date of accident Time of occurrence Causes of the accident etc What spatial analysis tool in ...
0
votes
0answers
97 views

Point Cluster Layer not defined

I am trying to do a point cluster layer based on the JSON objects I obtained from database. Here is my JavaScript to plot a point cluster layer: function addClusters() { $.ajax({ url: ...
1
vote
1answer
158 views

How to better visualize features of clusters in Openlayers

I am using the cluster strategy for mapping a large number of features in Openlayers, now I would like to find a good solution for providing info about the features contained in a cluster selected by ...
2
votes
1answer
76 views

Maximize clusters of points from coordinate data

So I am definitely new to the GIS world, so bear with me if I don't know the best way to articulate my problem. That said, I am ready to learn, I would definitely welcome any direction that you all ...
4
votes
1answer
180 views

XYZ Clustering in Python and numpy arrays

I am looking for a method of clustering XYZ data in Python that works on numpy arrays. I know of a few sources, such as clusterpy and Pysal but have had little success with them as they seem to still ...
1
vote
2answers
186 views

Is there a Cluster convex hull implementation in OpenLayers?

In this leaflet example. When hovered over a cluster marker, it shows the bounding area of the clustered features which is known as convex hull. Is there a way to reproduce it with OpenLayers?
-1
votes
1answer
66 views

Automatic Clustering in ArcGIS for Desktop? [closed]

Given a set of random data points on a map, I would like to cluster the data points based on number of data points in a cluster, time to travel within all the data points in the cluster,and/or number ...
0
votes
2answers
441 views

Explode clusters of overlapping points in ArcGIS Javascript API

In my map application built on ESRI's javascript API there are a number of points that share a lat/long. I need a way to allow the user to see all of the points at a specific location by exploding ...
3
votes
1answer
119 views

Spatial Classification

I am not sure what to call my problem. From this image, I have a set of classified polygons (colored). I would like a way to classify the white polygons in the image. I don’t have any attributes to ...