# Tagged Questions

The measure of separation between two entities or locations that may or may not be connected, such as two points.

52 views

### PostGIS distance between multiple points

I have a data set in a PostGIS data base (table name is animals) with the following structure: id (int, pk) | latitude (double) | longitude (double) | type (char) | geom (srid: 4326) In the type-...
34 views

### R script for find the minimum distance [closed]

I need an R code to select which polygon in a shapefile has got the minimum distance from a given point.
55 views

### Call gdal_proximity() from R

I have a raster including eight land cover types (pixel values ranged from 1 to 8): > r class : RasterLayer dimensions : 9887, 30532, 301869884 (nrow, ncol, ncell) resolution : 10, 10 (...
169 views

### Check if point is within radius of another point with Shapely

I've successfully used Shapely with python to check if a point is within one of a set of polygons in a .shp file but now would like to check if a point is within a circle of radius x miles from ...
38 views

### Calculate Geometry function returns underestimated distances

I'm making a map of the Colorado Trail and obtained a set of waypoints taken down the entire trail. I projected the set of waypoints from WGS84 (unprojected) to NAD 83 UTM13N after adding to the data ...
57 views

### How to calculate distance from point to nearest polygoin via road network (polyline) ARCMap 10.3.1

Using ArcMap, is it possible calculate distance from a postcode (point) to nearest polygon using a road network layer (polyline)? As opposed to just calculating Euclidean distance?
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### How to calculate shortest distance from start to end of river?

How can I calculate the straight distance from the start to the end point of a river (red line in image)? I don't know how to do this automatically.
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### How to I change the extents of a Euclidian Distance Raster?

I am calculating the Euclidean distance of a set of points. The output raster truncates the resulting raster image to the farthest north, south, east, and west point. I need the distances to extend ...
39 views

### Calculating distances (differences?) between two regions?

I am building a machine learning system which predicts the location of tweets as a bounding box (using the google maps API among other things). Since the twitter API also supplies a bounding box, I am ...
68 views

### Shortest distance over water in ArcGIS?

I'm using ArcGIS 10.2 with an advanced license. I'm trying to calculate the shortest distance over water between points (between survey locations at sea, and seabird colonies on land). I have a large ...
27 views

### Measure the distance between points automatically

How can I measure the distance between points referring to the same element in an automated way? In fact I've imported in QGIS buildings downloaded from two different sources and obviously they are ...
69 views

### Find distance from points along lines [closed]

I have two layers, one is a point layer of schools and another is a polyline layer of streets. The end goal is to create a buffer along the lines that is 20 feet from the centerline that goes 1 mile ...
53 views

### For Loop Maximum Minimum Distance Between Two Lines

I have a table of line/lane ids in a table called matched_lanes, and I am trying to create a lateral query that on each id in the table to find the maximumum minimum distance between each point. I.e....
41 views

### Counting points within range using CartoDB?

I have a dataset of users location and want to assign per user how many other users they have within a given range, and updating this value into a table.The dataset name is "users_20160410" and the ...
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### Network Analysis

I'm doing network analysis where i'm trying to analyze which point feature has the closest distance to a highway. I have created the points that I need and I also have the network dataset, but then i ...
22 views

### Calculating the distance between points and parts of a underlying raster set

I need your help with a calculation of the distance between points (cities in this case) and forest (raster data). Is there a possibility to collate to every city the distance to the nearest forest ...
182 views

### Drawing route on google map using gps device and calculating actual distance?

I Want to draw route on google map with the help of gps device and calculate the actual distance. Can anybody help with this? public GoogleAPIModel GetDistance(string origin, string destination) ...
31 views

### Node-line minimum distance: draw the minimum distance point location

I am working with a layer of nodes and a layer of lines. I would need a tool able to find and draw, for some couples node-line, the location of the closest point laying on the line to this node. ...
128 views

### Finding density centroids within polygons in PostGIS

I want to find the highest density of OpenStreetMap nodes within a dataset of census geometries. I want to tie the census data to the location of the node which is most central in terms of population. ...
36 views

### Discrepancy between CAD and GIS route lengths

I have imported a route from AutoCAD which is marked every kilometre and converted it into a shapefile. I put markers every 100 m using X-Tools. There is a difference between the two sets of markers, ...
73 views

### orthogonal projection of a point onto linestring in PostGIS

I am trying to find the orthogonal projection of a Point (in 4326 SRID) onto a LineString (in 4326). The picture shows the objective. I have tried to use ST_Distance function, but in this case the ...
154 views

### Given two lat/longs, how can I tell if they are within 1 mile of each other?

I'm trying to implement a very efficient check to see whether two points are within a mile of each other, or not. My current approach is to compute the Haversine distance, and then check to see if it'...
48 views

### Distance to nearest cell with value “x”

I would like to create a raster where each cell equals the distance to the nearest cell >= the value of the source cell plus a constant. In the example below, the input raster has a grid size of 1m x ...
75 views

### Generating random points near a location [closed]

In the following solution, why is there a sqrt(u)? Since u is just a random number in [0, 1) doesn't getting the sqrt just give you another smaller random number? To generate points uniformly, ...
41 views

### Looking for the “inverse” of the NEAR tool

To calculate wind fetch over water I need to create a point on the shoreline and then calculate the distance to to other shorelines all directions (0 - 360 deg). The shortest distance to another land ...
51 views

### Calculate shortest paths for each output area in catchment through road network to a single point (i.e. store)

The title sums it up pretty much. I'm looking to derive trip distributions to a single store using population data and distance within a prescribed distance catchment. I have calculated the catchment ...
42 views

### Point-Line shortest distance and corresponding angle using FME

I want to determine the shortest distance and especially the corresponding angle from a point to a polyline. A solution using FME would be strongly preferred.
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### Compare euclidean distance with network distance

I have a raster file with euclidean distance. It contains information about how long it takes for a chopper to arrive to certain destinations. I then have a polygon made from a service area with ...
56 views

### Pacific-wide Projection for distance?

I have a data set of ~3500 points located across the Pacific Ocean, and am looking to measure the distance from each point to it's nearest coastline to identify the "host" country. I had originally ...
32 views

### Finding distance of a building from road junction

I have a peculiar problem which i cannot think of way to solve. I need to find distance of a building from the nearest road junction. This would include distance to the nearest road and how far is ...
83 views

### How to calculate multiple travel times using gmapsdistance?

I am trying to use gmapsdistance on R to calculate multiple transit times from Google Maps. I have a Google API key and can generate transit travel times for one origin and one destination with the ...
77 views

### Measure distance between points along a line in QGIS

I have a road network and different points connected to the roads. I would like to measure the distance between several points along the roads. Basically I want to do the same like the road graph ...
23 views

### Computing intersection of distance circles around fixed points [duplicate]

(to simplify calculations, I assume a spherical earth. All distances are assumed measured "as the crow flies") Suppose we have the lon/lat coordinates for two points (p_1,p_2) less than Nkm apart. ...
286 views

### Shapely Distance different from Geopy/Haversine

I am running a specific analysis where we use shapely to create buffers around points (store locations) and then check if other points (user locations) are present within that buffer value. When i ...
37 views

### Finding distance between two points and land cover in %? [closed]

I am trying to use ArCGIS. I was using digimap to work out a 2km buffer from a sample point, I managed to do that and saved the file. I also saw some land cover types on the left hand side of Digimap ...
48 views

### How analyze reliability of position of new point based on point data

I am working on filter for biogeographical data. It is based on citizen science principle. People put new point data to database and I want add information about "reliability" or probability (maybe ...
310 views

### PostGIS get the distance between two points over a linestring

I have a linestring: LINESTRING(-1.3326397 50.9174932,-1.3319842 50.9166939) and I select two points that lay on that linestring. I would like to get the distance between these two points (in ...
85 views

### Calculate distance from a point to the border of polygon (US state)

I have a point, and I want to know if it is nearer than 100 miles from some US State border (California for example). I assume that I would need to use this: US Regions State Boundaries. But if I ...
29 views

### OpenLayers measurment path in 31700 projection

I have this code who works great for distance measurment on 900913 projection with 4326 display projection (bing maps + layer WMS): measureDistanceControl = new OpenLayers.Control.Measure( ...
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### Incorrect results returning from st_distance_spheroid query

Given a routable network table constructed by completing the guide at http://anitagraser.com/2011/02/07/a-beginners-guide-to-pgrouting/, how can I get an accurate list of all roads that are within a ...
53 views

### cells w/in search window GRASS GIS

I am trying to find all cells that are a certain distance and within a certain window from a cell of interest. For example: I want all cells in a distance of 10m within a search window of 10 - 40 ...
45 views

### How many query points fall within distance X to a set of LineString

I have a set of 10 query points and I want to know how many of them are with distance within at most 4 meters of any LineString in a given table. Note that if a point is within 4 meter distance to ...
27 views

### Using “snap pour point” to find a watershed of specific area starting from a point

I am trying to find everything downhill of a certain point in order to create a watershed of a specific area. For example, say I have a point at (x,y), and I'm interested in creating a watershed ...
76 views

### How to measure the Speed between two Waypoints?

I'm totally new to QGIS or any GIS. I need to analyze a lot of Waypoints to get the average speed of the people walking between them. (It's for analyzing an experiment I made) therefore I neet do ...
41 views

### Calculating distance between points from table of UIDs [ArcMap]

I have a .dbf file containing pairs of point feature Unique Identifiers (UIDs), and need to calculate the straight-line distance between each of these pairs. The XY coordinates of the individual ...
148 views

### How big does a circular geofence need to be for the curvature of the earth to matter? [duplicate]

I'm working on adding geofences to a mobile application. I know the proper way of calculating distance between two points on a sphere is using the great-circle or Haversine formula. I don't know if ...
28 views

### EPSG:4978 or others for Distance

Usually when I have been calculating distances I project to the system which has the tightest crop around my points e.g. for the UK #http://epsg.io/27700-5339 (accuracy: 1.0m) uk = '+proj=tmerc +...
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### Build network based on shortest distance between points

Is there a way to build a network based on the shortest distances between each point of a point layer. I have occurrence data from species (as points) and want to estimate whether there are one or ...