Questions tagged [clustering]

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

104 questions with no upvoted or accepted answers
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QGIS/Spatialite cluster analysis with density

beginner here I am trying to analyse a large set of points (2 millions) over a set of polygons (3000), and particularly find clusters of points. Doing it in QGIS was taking too long/crashing the ...
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241 views

Grouped “labels” for QGIS 3.0 Point Cluster styling?

I'm trying to make a cluster visualization of a vector point layer about trees with a few requirements: The clusters need to change depending on zoom level (solved) The clusters need to indicate how ...
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206 views

Enforcing maximum distance with ST_ClusterWithin?

I have a set of location points and I want to find clusters within the set. This is fine. However, I don't want to get two points in the same cluster that are farther apart than the maximum distance, ...
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1k views

Clustering of events within a space-time window (R)

I am relatively new to clustering methods and am trying to determine the best method for clustering (or merely grouping) events that fall within a space-time window using preferably R. My goal is to ...
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126 views

Comparison of clustering methods on geodemographic classification

Most geodemographic classification systems using K-means method for clustering and creating segments. For example, ESRI Tapestry(Business Analyst) is most using geodemographic system lately. What ...
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562 views

Query a different density of points based on zoom level in PostGIS

I have a database (using PostGIS) of a few million points that I load onto an interactive map. Obviously the map can't handle this many points, so I currently restrict it by limiting to the points ...
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224 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 ...
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59 views

Clustering based on eqaul populations

I have a map of a city that is divided into 65 sectors (building lots in purple, sector boundaries in red): In my shapefile of building lots, I have an attribute that is the total population within ...
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172 views

Find number of weighted point clusters & centre of clusters

I have a points layer with a frequency field indicating a population at that point. There is also a field indicating the broader area by which I need to analysis broken down into. I am expecting the ...
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819 views

Can't clear markers from MarkerClusterGroup

i have problems removing all markers befor adding new ones. var L_Emergency_Access_Points = L.markerClusterGroup(); var EapMarkers = L.geoJson(null,merge_options(globalOverlayOptions, ...
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80 views

Scaling postgresSQL database when searching polygons against points?

I am using our single server - CentOS 6.6 x64 16 CPU 24 GB SSD (PostgreSQL) 9.4.1 as our GIS database processing engine. This is part of the PostGIS software package installed on the server. I am ...
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98 views

Perform cluster with point limit?

I have a layer with about 250 points and I need to group them into groups of 30 points. How could I perform this operation in QGIS? I researched on plugins and clustering techniques and the most ...
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3k views

K-Means clustering in QGIS (Attribute based clustering)

In the 2.18.4 and 2.18.5 version of QGIS K-means clustering was moved to a plugin called 'Attribute based clustering'. However, I am working with a virtual raster dataset (vrt.) and the current ...
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412 views

Spatial clustering with attribute

I need to do some sort of spatial clustering where each spatial coordinate has a value attribute. So, for example, each point has a salary attached to it. So each cluster would have a total salary if ...
3
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1answer
869 views

How to Construct Spatio Temporal Clusters of Time Series Data in R

I have count data of one disease for various districts of a state of India on monthly basis. Is it possible to draw spatio temporal clusters in R? I have checked some R- packages for example ...
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59 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
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64 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 let'...
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605 views

Geoserver Clustering Problems

I have problems setting up a clustered Geoserver. So far got four instances (version 2.2.4) running on a ubuntu linux box with a shared data directory behind HAProxy. I use one of the geoservers to ...
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1k views

How to show information window for the marker cluster?

This is my markercluster code : i need information window for the markercluster icon as well as marker icon, i have another cluster.js file, can some one please tell me how can i show the information ...
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40 views

Displaying sum of field in cluster symbology using QGIS?

Using QGIS, I have a point layer of wind turbines. One of the fields is MW (megawatts produced by the turbine). I want to display the turbines by clustering. But I to show the sum of MW in the ...
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23 views

Importing hdbscan in QGIS plugin?

I am building a QGIS plugin and would like to add hdbscan in methods. But when I import with OSGEO4W shell it failed at this line: File "C:\OSGeo4W\apps\Python37\lib\site-packages\hdbscan-0.8.22-...
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0answers
23 views

Clustering raster based on area of specific number of pixels

I'm currently looking at overflows of rainwater in a region and I want to find all the puddles, which have a restricted size and a minimum number of pixels in them and create a vector layer where each ...
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85 views

Rank-based Spatial Clustering in Python

I was wondering if there was any python (or R) packages out there that can do spatial clustering on ranked data? For each US state I spatially varying value for education rankings. For example, for ...
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387 views

PostGIS - Dynamic Server-Side Clustering based on Zoom level

I'm working on a Ruby on Rails application that is showing road signs on the map(leaflet). So, user can browse map and road signs, great. But, if there are a lot of signs and user wants to zoom out, ...
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153 views

Cluster Points on spatial network in R/QGIS

I am searching for a method for clustering spatial points along spatial lines. The points are connected to the lines. I tried nearest neighbour clustering and gProject/gInterpolate from the rgeos ...
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192 views

Smoothing borders of polygons taking a layer of points into account

I'm trying to smooth borders that separate clusters of points. GRASS instrument v.generalize.smooth works pretty well, except that in some cases the points end up on the wrong side of the smoothed ...
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527 views

Is it possible to color the cluster base on marker color?

So far, I've been able to generate the marker color base on query from my MySQL DB. What I would like to attempt now is to cluster those markers with the dominant marker color. For example, if I ...
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3k views

Clustering latitude longitude data based on distance

I have a large dataset of latitude and longitude. I want to cluster the data into groups based on distance such that the distance between two points in a cluster is not greater than a minimum ...
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0answers
328 views

Identifying activity places in GPS trajectories using R?

Is there a way in R (a script or package) that would allow identifying activity spots in GPS tracking data? I have a number of GPS tracks in GPX/CSV formats that follow the movements of people in a ...
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0answers
550 views

Displaying markers instantly when loading in cluster?

I am loading a big json for about 10000 pins with some text, about 3-4mb. And it takes some time to load all the pins and display them. Is there a way to diplay the pin right after loading? So to ...
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163 views

k nearest neighbour with count limit

I have a set a points, and I want to create 10 clusters. I used attribute based clustering plugin, which worked well for creating the clusters, but the points count isn't perfect, some clusters have ...
2
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0answers
182 views

How to find peaks by comparing with neigbhour points

I have a raster layer with 3 bands band1 - elevation data band2 - x-coord band3 - y-coord I want to run  a grid of 9*9 cells over this raster layer staring from top-left to bottom-right row-wise ...
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837 views

Is it possible to cluster markers based on city name in Google Maps API

I have a requirement to display all the customers in map. Since the customer list is too large it looks messy when I place markers. I have tried the marker cluster functionality but it groups based ...
2
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156 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 ...
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164 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 ...
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20 views

Defining Parameters using Spatially Constrained Multivariate Clustering of ArcGIS Pro

I have a point shapefile with 51673 features. I am trying to cluster them using the Spatially Constrained Multivariate Clustering tool in ArcGIS Pro. After reading through the documentation, I'm ...
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24 views

Providing a qualitative description of the results from DBSCAN clustering

I have run a DBSCAN clustering algorithm in QGIS 3 on bus stops in my specific study area where my minimum cluster size is 50 and maximum distance is circa 9km. After this I created a concave hull of ...
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1answer
45 views

Speed up GeoJSON clustering and rendering?

I am rendering 10,000 points with Leaflet's markercluster library. I fetch these 10k points from our server. This takes about 700ms. It takes Leaflet about 3 seconds to cluster these points and ...
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77 views

Change maxZoom level on Leaflet Marker Cluster Group?

Our leaflet web app allows users to switch between tile layers. The tile layers sometimes have different max zoom implemented by the tile provider or local config. We have another layer with ...
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50 views

QGIS > Concave Hull plugin > Shared Nearest Neighbor Clustering

I have been using the Concave Hull plugin in QGIS & the Shared Nearest Neighbor Clustering feature. I am having issues with this plugin, each time I choose the option of "Number of Neighbours" it ...
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0answers
28 views

Leaflet.TimeDimension and Leaflet.Marker.Cluster

I am trying to combine L.MarkerClusterGroup with L.TimeDimension: basically, I would like to load a geoJSON and control the appearance and disappearance of points with L.TimeDimension, but in such a ...
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0answers
52 views

Simple clustering example

I'm trying to use postgis ST_withincluster function. But my knowledge over SQL seems a bit too fresh at the moment and I can't figure out by myself how I should proceed by reading posts like this one: ...
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1answer
159 views

K-means clustering in QGIS with statistically significant difference

Anyone knows that how to do K-means clustering with significant difference? What I means is as the image shows, the area is divided into two zones using k-means clustering, and the significant ...
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45 views

Merging and Clustering Rasters using QGIS?

I have 3 rasters for three regionalized variables (r1, r2, r3). The rasters have the same projection, origin and cell spacing. Can I merge this into ONE "multivariate" raster? (ie x,y,r1,r2,r3) I ...
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200 views

Cluster points into evenly numbered groups

I need to take x number of points and equally/spatially divide them into groups. Meaning that if I had 40 points like in the image below and wanted to have 4 groups of points. Each group should have ...
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1answer
189 views

Performance issues with (clustered) point features

How do I get a point features layer containing roughly 2800 labeled features to perform smoothly when exported (and converted to GeoJSON) with qgis2web? Specifics: I use qgis2web 3.4.0 and QGIS 3.2.3 ...
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0answers
137 views

Cluster LineStrings using HDBSCAN?

I am trying to cluster a set of LineStrings (made out of lat/lon Points) with the help of HDBSCAN (using the "haversine" metric). The objective is to define the most "usual" path. I have only managed ...
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176 views

Using output of unsupervised cluster analysis to train supervised classification for vegetation mapping?

I'm using Google Earth Engine to classify mangrove forests from Landsat imagery to calculate extent. Let's say I perform an unsupervised K-means cluster analysis on a Landsat scene to identify general ...
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0answers
52 views

Split shapefile to approximate area

I have a shapefile with multiple polygons of different sizes and want to split this shapefile to new ones trying to achieve a determined area, but without splitting any polygon. For example: I want ...
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0answers
193 views

QGIS - Distance between cluster analysis not working with K means and taking to long with hierarchical method. Any advice?

QGIS- Trying to carry out a cluster analysis regarding the density of villages in Kazakhstan. I am placing latitude and longitude as my fields and not sure if this is correct (see image). ...