Questions tagged [distance-matrix]

a distance matrix is a matrix (two-dimensional array) containing the distances, taken pairwise, of a set of points.

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PGrouting number of results in pgr_dijkstraCostMatrix() not right

When running the pgr_dijkstraCostMatrix() on a PostGIS database with 41000 id's I get only 144000 rows in the matrix. I would have expected much more. What am I missing? I parsed the OSM data with ...
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Given a table of distances, how do I distribute distances to minimize them between points of interest?

A little domain specificity first: I work for a nonprofit which runs a high school program for the American Legion. I’m trying to “assign” high schools (338) to local American Legion Posts (126) based ...
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32 views

Grouping layers by attribute value and finding nearest neighbour using QGIS?

I am new to QGIS. I have two layers (layer_a and layer_b) consisting of two sets of points. If I want to find the nearest point in layer_b for each point in layer_a, I can just use the Distance ...
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Solving ‘Null geometry…’ error during distance matrix operation?

I have a tab delimited file with data about earthquakes epicenters and their intensities (signif.txt). I also have a shape file with point data representing populated places of the world (...
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Fail to conduct resistanceGA with run_gdistance

I am using a landscape surface resistance distance counting R packages called resistanceGA It can count commuteDistance with the assistance of another package gdistance It uses the following code to ...
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Calculating distance from centroid points to multiple polygon edges with SpatialLite

My question builds on a question previously asked (Calculating all distances from single points to multiple polygons). User @alexandre-neto provided an answer that I've worked on, but it isn't giving ...
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Point-distance analysis using time as an attribute

Is it possible to calculate "points within a certain buffer zone" for each point in a vector layer and do this by controlling time as an attribute field? I would like to analyse morbidity densities of ...
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71 views

Travel Distance Calculation in QGIS

What is the best method calculating travel distance between destination and point layer in QGIS when using OSGB 1936 / British National Grid coordinate reference system?
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76 views

Fetching the nearest location of points, while accounting for bodies of water

I've got a database of points (in this case, schools) and in my app, users search for the nearest ones to them. Under the hood, we're currently using ElasticSearch to filter by latlng (using Geo ...
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104 views

Points Layer to Distance Matrix QGIS 3.6 - Noosa

I'm trying to calculate a sample distance matrix from four points in the BNG CRS: Using Vector-> Analysis Tools -> Distance Matrix, I get: Input point layer is a MultiPoint layer - first convert to ...
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Finding nearest distance between point and polygon layers in QGIS

I am using QGIS to undertake an analysis for a project. This involves a polygon shapefile, which represents a boundary of a site, and a series of points which represents the location of parks. I ...
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165 views

dist2Line - Error in dist2Line(…) could not find the function “dist2Line”

I have a csv file with points (about 20 millions georeferenced points) and a line shapefile. I want to find for each point the closest distance to the line. The line is not a straight line it's ...
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48 views

Measuring Distances between Points with the same timestamps using QGIS

I'm facing the problem that I want to calculate flight distances of Red Deer. I have a Layer with point Locations of animals; One attribute is the timestamp. I have another layer with point locations ...
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Distance matrix in QGIS shows distance zero to all points

I'm using QGIS version 3.4.2-Madeira. I have a point layer with 96 points in Germany and I want to calculate the 3 nearest neighbors of every point. I know this can be done with the Distance matrix ...
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QGIS: Distance matrix between points, constrained by a polygon

I am looking for a way to calculate a distance matrix between points, but not 'as the crow flies'. I want the distance to be calculated around a polygon layer. Example 1: I have several fishing lodge ...
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538 views

Getting the departure time based on a desired arrival time for driving

Context: I'm working on a logical problem as part of my Msc. thesis in GIS. I want to calculate the departure time (output) based on a desired arrival time (input). I have chosen to use an API to ...
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73 views

What do you call a map that shows the closest distance to a set of points?

This is one of those hard problems to Google since I don't know the right words to Google! I have a list of 6,000 retail locations in the US, and I want to know, for any given point, how far away one ...
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84 views

QGIS Distance Matrix Output is always consists of zeros?

I have a shapefile with 35 points and I try to have the distance matrix showing the distance of each pixel with each other. I choose the input and the target file the same and the unique ID fields are ...
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164 views

Excluding point from Nearest neighbor search once it's been matched using R?

I have two lists of addresses, List 1 and List 2. I want to find the nearest neighbors of the list--but without assigning more than one point to any point. So say point 1A is the nearest neighbor of ...
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268 views

Distance Matrix with 2 point shapefiles and one street network

I have two point shapefiles (start/destination) and one sort of street network shapefile. I would like a to create a distance matrix from the start-shapefile to the destination points, using the ...
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220 views

Distance matrix (nearest neighbour) with polygons

I would like to calculate the closest distance between polygons in the same layer. The "distance matrix" tool only accept point layers. Is there a (easy) way to calculate the distance between edges ...
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313 views

QGIS Distance Matrix - with line geometry output?

I have a series of Output Area centroids and I want to create a matrix of lines between each point (every point connected to every point), which is effectively what the distance matrix tool does (I ...
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165 views

Find the nearest neighbour for points in one layer to points in another, then measure the distance

USING QGIS 2.18.19 with python console (planning to upgrade to the newest QGIS after this piece of programming) I am struggling with finding the correct pyQGIS coding for this. I have a shapefile ...
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1answer
167 views

Getting distances between mutiple points and one “central” point using QGIS?

I have a GPS data including static measurements and would like to look more in detail on those static ones. Is it possible to take the point cluster from one measurement (I can extract it by time ...
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191 views

QGIS Distance Matrix execution fails

I am trying to use the distance matrix to measure the distance between a crime (input ID) to the closest subway entrance (target layer). The problem is that sometimes the matrix comes out with results,...
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408 views

Distance Matrix output

I'm using QGIS 2.18 Las Palmas, and I'm trying to build up a Distance Matrix of a series of points for a Mantel test. Specifically, I have a series of points and I want to calculate the distance of ...
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990 views

Creating a distance matrix for line and/or polygon layers?

At 2.18.16, the QGIS tool Distance Matrix computes pairwise distances between all points, either within one layer or between two layers. Here's a screenshot for a single layer. Note that only points ...
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161 views

Is there a standard measure of Remoteness?

I have a number of sites around the globe, and they are not uniformly distributed. I would like to use some measure of remoteness, in order to compare sites that are more or less remote. I guess ...
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79 views

QGIS-bin.exe stops working when trying to run NN-Join

I am trying to calculate nearest neighbor using the NN-Join add-in. This has worked well until now, but after I updated my data it only partly works. I have a point layer, and I have three other ...
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349 views

Calculate distance matrix based on network

I have the following layers in QGIS: origins points destination points a layer of lines that is the route I want to calculate the matrix with the distance from origin to destination using Network ...
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70 views

Distance matrix batch process for different area types in one layer

I have a layer of the centroids of all neighbourhoods in a city, with neighbourhood ID and borough ID as attributes of each point. The city is made from boroughs, which are themselves made from ...
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821 views

Calculate distance matrix in km units

I would like to create a distance matrix and have as output the distances expressed as kilometers (km). Here my current output, which I believe is in degrees and NOT in km: My coordinate system (CRS)...
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161 views

Network Analysis of Multiple points

Is it possible to do a network analysis along a path (road) from multiple points to one point in QGIS? I am trying to calculate the distance from the center of various suburbs to the city center. ...
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118 views

mean coordinates and measurement of distances

I am trying to find a location that minimises the total distance to a series of points, and compare it with the distance to an existing location. I used the QGIS tool mean coordinate(s) to calculate ...
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1answer
71 views

Why does my RAM cap out around 150 MB when doing the Distance Matrix analysis in QGIS?

I am currently trying to determine the 2 nearest points for a database of 8 million people against 425 locations. I have 2 csv files uploaded into QGIS one with a unique number for 8 million people ...
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467 views

Calculating shortest distance between points within polygon using QGIS?

I performed a transect in which I sampled several animals. The location of these animals are represented by a point shapefile. I am interested in calculating a pairwise matrix of distance (in meters) ...
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1answer
140 views

How can I use Distance Matrix tool in QGIS with metric distance for global data?

I have 2 point layers spread out all across the globe. I would like to use the Distance Matrix tool, and would like to get the distances in metres or kilometres. I'm aware that I have to change the ...
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73 views

How do I measure shortest distance where it crosses +/- 180 (the International Date line)

I'm trying to measure the shortest distance between two sets of points on the globe in QGIS. One set of points is close to -180 and the other close to +180, QGIS Distance matrix is giving me a ...
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Estimating road network distances when database queries are expensive

I have a large number N of points and I'd like to build their distance matrix with respect to a road network. Unfortunately, I am not able to perform all N^2 queries to build this matrix, so some ...
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4answers
644 views

Creating a Point at a specific distance between two Points

I am trying to create a new point shapefile and I am unsure how to create it. I want to create a new series of points that would be based on a specific distance between two points in an existing ...
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92 views

Obtaining contiguity matrix from layer of polygons using ArcGIS Desktop?

I have a layer of statistical areas, and would like to obtain the contiguity matrix, that is, the matrix W in which an entry w_ij equals 1 if i and j are neighbors (share a border) and 0 otherwise. ...
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1answer
434 views

Distance matrix returning incorrect values in QGIS 2.18

I'm having issues with the distance matrix tool in QGIS 2.18 giving output distances that do not match the distance using the measuring tool. I've checked previous threads and so far can't find an ...
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175 views

Need to calculate distance (Node to Node) along the lines [closed]

I have a Shapefile (polygon), I need to calculate distance (Node to Node) along the lines in map unit(meter or kilometer). I want to do it in ArcGIS.
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1answer
814 views

Distance Matrix PostGis

Assuming I have a table or 2 dimensional array with only geometries and names (all in all 5k elements) name the_geom a polygon_geometry.... b polygon_geometry.... c ...
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252 views

Calculate Great Circle Distance between two point layers via way point

I need to create three distance matrices for around 550 points spread throughout Africa, Europe and Asia. The first matrix represents great circle distances, the second is the shortest distance along ...
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2answers
56 views

Error in pairdist calculation

I'm trying to calculate pair distances among the points of my dataset. I have point in EPSG:3857. This is the code I ran: I import the data, then: coordinates(datPb) <- c("X","Y") proj4string(...
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434 views

Where has the 'distance matrix' tool gone in QGIS 2.18.0?

Today I installed QGIS 2.18.0 and I wondered, where has my 'distance matrix' - Tool gone?
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2k views

QGIS Distance Matrix Output

I have a shapefile of points and want to measure the distance between each of them. After running the Distance Matrix command I get a matrix with distances as expected, but have no idea how to match ...
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317 views

Using Proximity tool in QGIS 2.16

I am using the proximity algorithm to generate a raster proximity map indicating the distance from the coast (points shapefile) of my study area and the center of each planning units (I have divided ...
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1answer
364 views

Problem with units in distance matrix after projection change in QGIS

In QGIS 2.16.3, I have a point file, originally in the WSG84 (EPSG:4326) projection. I wish to determine the distance in km between each point in this point layer and intend to use the distance matrix ...