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

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3
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1answer
213 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 ...
3
votes
2answers
207 views

Methods for hot spot or cluster analysis for multiple measurements at the same geographic unit?

I would like to find geographic clusters of zip codes where each zip code has a measurement of a person's age (integer), sex (categorical/binary), and if they recovered from a certain medical ...
3
votes
2answers
423 views

How can I GROUP BY linear spatial clusters with PostGIS?

I have a series of points in a horizontal line, arranged into discrete spatial clusters by the underlying data pattern. Here's an example of what they look like: How can I use PostGIS to group them ...
3
votes
1answer
780 views

Find clusters of points based distance rule [duplicate]

I have some points that I need to divide into groups based on clusters of points: x <- c(-1.482156, -1.482318, -1.482129, -1.482880, -1.485735, -1.485770, -1.485913, -1.484275, -1.485866) y <- ...
3
votes
1answer
148 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 ...
3
votes
1answer
864 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 ...
3
votes
2answers
1k views

Cluster Strategy different Labeling at Different Level

what I did? I am trying to plot some points using cluster strategy of openlayer using animatedCluster plugin. I have gson data as given: { "type": "FeatureCollection", "features": [ { ...
3
votes
1answer
829 views

toggle clustering with map controls

I've made a map with openlayers and have the vector features clustered with a clustering strategy. Now I want my users to be able to toggle this behaviour with a control similar to the layerswitcher. ...
3
votes
1answer
455 views

How to access the icon of a feature retrieved from text in a vector-layer?

I`m using OpenLayers to show POIs on a map. These POIs are loaded from a textfile and I`m using a Vector Layer to get it onto the map - works great. Now I want to use the cluster strategy to have ...
3
votes
1answer
2k 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 ...
3
votes
2answers
209 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 ...
3
votes
1answer
41 views

Analyzing hot spots using point attributes?

I'm interested in looking at where hot and cold spots of certain social indicators (such as poverty, housing characteristics, urban sprawl, etc...) are in coastal communities along the East Coast. I ...
3
votes
1answer
103 views

Hot Spot Analysis using ArcGIS for Desktop?

I have a point shape containing locations of cars and a line shape containing roads. Now I want to identify hotspots/clusters. I want to find hot spots where for example the speed of the cars is ...
3
votes
1answer
130 views

Is it possible to distinguish between points with the same coordinates?

I have several points with the same coordinates in one layer and of course they are located on top of each other. Is there a way to separate this points automatically (not manually)? I don't want to ...
3
votes
2answers
2k views

Dynamically adding features with cluster strategy

I am trying to dynamically add features to a vector layer, and use cluster strategy to group those features accordingly. I am able to do this for the first set of data that gets loaded on the map. ...
3
votes
1answer
2k views

How to cluster 2 datasets in Google Maps API V3?

I'd like to produce a map that shows thousands of Markers. I'm using Markersclusterer to show all these markers. Yesterday, I received another huge data set (completely different) and I'd like to see ...
3
votes
1answer
49 views

Geoserver clustering

I am running into problems configuring the jms clustering of Geoserver. Here is the background: I have 4 virtualboxes, each running a Geoserver 2.7.1 with the jms-cluster extension. I would like to ...
3
votes
0answers
40 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 ...
3
votes
0answers
38 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 ...
3
votes
0answers
40 views

Clustering driven by an enum/list

Given a set of 2D points ( or vertices if you want ), the values stored for each point are: coordinate on x coordinate on y an enum or a value from a list in general for the sake of this example ...
2
votes
2answers
600 views

A lot of pointers to load on map-A better solution

I have to project a lot of points present in my Database say more than 100000. I heard that using geoserver is a better solution as it can render any number of points and from ...
2
votes
2answers
555 views

Merge nearby items into a single representation

I'm investigating OpenLayers and I'm trying to see if it's possible to filter down the number of displayed feature items. Is it possible to display many nearby items as a single point item on a map ...
2
votes
2answers
547 views

Is it possible to generate a heatmap on the server-side using ArcGIS Server?

Using ArcGIS Server's JS API it is possible to generate a heatmap at runtime, as in the example at http://tmappsevents.esri.com/website/heatmap/index.html This requires having client-side access to ...
2
votes
3answers
555 views

Server side clustering - cluster (feature) geometry

I am trying to implement server side clustering and show it using OpenLayers. I am using this good material as an example. As a clustering result, a get some list of features, some of them are ...
2
votes
1answer
93 views

How to cluster points into clusters of a maximum diameter in PostGIS?

I'm working with transit stops in GTFS. I want to group together stops (N~8000 for a medium sized agency in the USA) which are proximately related in order to reduce the number of dimensions but also ...
2
votes
1answer
111 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 ...
2
votes
2answers
455 views

Show different marker for cluster and icon for single vector features in OpenLayers

I have a vector layer which is geoJSON file containing school points and their attributes,to visualize this i defined cluster and show circle which size is based on the number of features it contains. ...
2
votes
1answer
3k views

How to get Openlayers cluster strategy work for large data?

The map Layer has around 1500 points. I am able to display all the points in the map without any problem but adding the cluster strategy to the layer does not work. The Cluster strategy functions when ...
2
votes
2answers
227 views

Remove clumps of pixels in R

I would like to remove isolated pixels (or clumps of pixels <9) from my raster image. library(raster) # create some raster data r <- raster(ncols=12, nrows=12) set.seed(0) r[] <- ...
2
votes
1answer
353 views

How to not overlap cluster popups with FeaturePopups control?

FeaturePopups control resolve the problem of cluster popups, but there is a small design problem in my opinion: the event popup have the same anchor as the cluster popup and they partial or total ...
2
votes
2answers
2k views

zoom to cluster onClick & have hover event

I've made a simple mock-up trying to combine two openlayers examples. I want to have clusters on which I can hover (so I can display an infowindow about it's content) and I want users to be able to ...
2
votes
1answer
444 views

Clustering Point for StatePlane WKID 2236

Does anyone have an example to point me in the right direction to utilize Clustering with the ESRI JS API working with a State Plane wkid: 2236? I want to provide a solution for an internal ...
2
votes
1answer
63 views

Create a grid with statistics of the merged shapefiles in QGIS

I operate with QGIS. I have to split the shape files of the buildings and the roads of a city into a grid of 500x500m per square and into each square I have to obtain the total free area, the total ...
2
votes
1answer
78 views

clustering map (North, Centre, South) in R

I am looking for a method to partition map in 3 groups (North, Centre, South) like this: how to do this in R please stations.txt Code : Al <- shapefile("DZA_adm/DZA_adm0.shp") # read in ascii ...
2
votes
1answer
364 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 ...
2
votes
1answer
378 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 ...
2
votes
1answer
301 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 ...
2
votes
1answer
119 views

Matching two point clouds without loss (nearest neighbor, but more complicated)

I have two point clouds, one with demographic and one with electoral data. Points in both clouds represent the same empirical entity (say, a village, or an urban neighbourhood), but are not in the ...
2
votes
1answer
121 views

OpenLayers, Get clustered point's val

I'm working on a map with WMS overlays and a lot of markers, my problem is when I try to calculate the average of points clustered, I've found how to differentiate the behaviour and the label text ...
2
votes
1answer
169 views

Fast Clustering Algorithm for Geographic Data?

I have been browsing through the net in my attempt to find a fast clustering algorithm to cluster geographic points, but lot many of the results found were for clustering algorithm in general and not ...
2
votes
2answers
2k views

How to merge/cluster smaller contiguous polygons to form larger ones?

Any help you can give an inexperienced college GIS user would be greatly appreciated. I am using both ArcGIS ArcMap 9.3 and 10 on desktop (i.e. not online), and the only info I can find on License ...
2
votes
2answers
861 views

Distribute ArcGIS services across multiple servers

What do you do when you have so many published services in ArcGIS that running even one instance of each service maxes out RAM/CPU? We've grown to the point where we have more published services than ...
2
votes
1answer
686 views

Clustering not working on features in OpenLayers

I've built a mapping solution using OpenLayers that works well except I can't get the points to cluster. I've looked at the examples on the site, and I've even implemented those examples in my ...
2
votes
2answers
239 views

Remove duplicate names in FeaturePopups cluster tooltips and popups

I am using FeaturePopups control to show tooltips and popups for clusters. I have features connected (ends of road segments) with the same names. Is it possible to remove them from tooltips and ...
2
votes
1answer
121 views

DBSCAN gives “AttributeError: NoneType has no attribute issparse”

I am running a Python script invoking the DBSCAN tool to cluster feature points. When I open ArcMap, load the feature layer, and run the script, it works the way I expect it to. But if I run it ...
2
votes
1answer
111 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 ...
2
votes
1answer
149 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 ...
2
votes
0answers
88 views

Determining spatial cluster of park types in ArcGIS

Question 1: I am trying to determine which (if any) of my different park types are spatially clustered across my study area (city boundary). There are 162 total parks, 9 nominal categories (which ...
2
votes
0answers
124 views

Installing knn on PostgreSQL for windows

I am trying to install the extension KNN for clustering as an extension on my PostgreSQL database. I have downloaded the file http://www.pgxn.org/tag/analysis I found instructions on how to ...
2
votes
0answers
182 views

How to cluster features based on their proximity?

I have around 500 features (Forests) that I want to cluster based on their proximity, and then work with those clusters. I only have the ID, and shape area of those features. How can I cluster them?