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

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27 views

Calculating average raster to point distances within census tracts

I have some experience using ArcGIS, but mostly with the field calculator in the attribute table/spatial joins, so I apologize if I say something that doesn't make sense. To provide a bit of ...
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0answers
16 views

How to create an attribute table from a Euclidean Distance Raster?

I am trying to create an attribute table from an Euclidean Distance Raster. I get the following error: "error 000423: Only single band integer dataset is a valid input". The ED Raster has actually the ...
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1answer
25 views

Distance to object, taking into account size of object

I have a number of polygon features on the edge of a lake feature. I also have sample points throughout the lake feature. I am looking to add some sort of indicator for these points as to how ...
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1answer
23 views

SQLite db with FDO geometries: how to assign ID of point in layer A to closest point in Layer B with SpatiaLite?

How can I assign ID of point in layer A to closest point in Layer B with SpatiaLite (find nearest neighbors for each point in A)? For each point stored in table fdo_fc1 I would like to select one, ...
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1answer
56 views

Merging rasters which overlap using ArcGIS for Desktop?

I need to merge two rasters which overlap, both indicate distance values. I need the output of the merge to result in the shorter/lower distance value. I am using ArcGIS 10.1. I hope it is more ...
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1answer
35 views

How do I generate a distance table using 2 different point files and a line file?

I have two point datasets, one containing multiple transit stops and the other containing multiple schools. I also have a street line dataset. I need to generate a table that gives me the shortest ...
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1answer
40 views

Postgis ST_Distance query returning inaccurate results

I am using the following query to retrieve records from a postgresql DB @services = Service.select("*, ST_Distance(services.lon_lat, ST_GeomFromText('POINT (lat lon)', 4326)) as ...
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1answer
67 views

Proof of part of haversine formula?

I'm trying to study how to find the distance between two points if their latitudes and longitudes are given. I have a question about the proof of part of the haversine formula given at Math Forum. ...
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1answer
3k views

How to find nearest point for each point in current layer using ArcGIS Desktop?

I have a point layer and want to know the distance of nearest point of current layer for each point in the layer. I found some tools in ArcToolbox about it , but they need two layers for input and ...
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4answers
7k views

Calculating the minimum distance between points and polygons in QGIS

I have two vector layers: one point and one polygon and I want to calculate the minimum distance of each point from the polygons (ie the distance from the closest point of the closest polygon). Is ...
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1answer
41 views

Calculating Distances Between Geometry Columns of Differing SRIDs

I am attempting a relatively simple task but have been running into trouble. I have two tables, one which has lat and lon points which were geocoded using google (SRID 3857) and another table which ...
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1answer
61 views

Calculate longitude length in miles

Suppose I have geographic coordinates of "Saratoga, California, USA" as Latitude: 37°15.8298′ N Longitude: 122° 1.3806′ W I know from here that in case of latitude 1° ≈ 69 miles and that ...
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0answers
40 views

How to calculate the average point spacing for a layer of points in QGIS?

I have a set of points and want to calculate the average point spacing for further analysis. ArcMap has the 3D Analyst Point File Information for this but I'm searching for an alternative in QGIS. ...
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1answer
701 views

How to calculate driving distance/time between two points

I am doing some analysis for our fire rescue department where we are comparing actual response times to fires vs predicted response times. The actual response time analysis is straight forward as I ...
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1answer
46 views

QGIS Azimuth and Distance plugin length issue

Relative newbie to QGIS and trying to figure out exactly what I'm doing wrong. A couple days ago I had azimuth and distance working perfectly. I was using it in a different project with different ...
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3answers
435 views

Toblers's Hiking Equation and Slope Dilemma

I'm trying to use Toblers's Hiking equation to determine economical backgrounds of some hillforts. The equation is anisotropic which means that the speed of movement that it calculates differs whether ...
2
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3answers
420 views

Draw line between points from multiple datasets

I have 2 point datasets and want a tool or script to draw a line between all points in one dataset to all the points in the 2nd dataset. Is it possible? I have tried ESRI "Point Distance" and ...
2
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1answer
76 views

Distance to nearest hub output not correct

In QGIS 2.6, I'm working with two point layers: center of the population per census tract and stores that accept food stamps. I'm using "distance to nearest hub" to calculate nearest food stamp outlet ...
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2answers
106 views

Cost-Distance Tool not producing logical answer

I am working on creating a cost catchment based on Tobler's equation in ArcGIS10.1. I feel confident in my cost surface; it produces a raster where each cell equals the time in hours that it would ...
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2answers
1k views

Postgis, get the points that are x meters near another point, in meters

I'm trying to find the points within a certain distance, in meters, from another point. I'm using the function ST_Buffer, but I don't get how to express the distance in meters. I'm trying with ...
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1answer
148 views

How to set the length of a line using openlayers

I'm trying edit a polygon by changing the length of some lines by code. Found this method to calculate based on the bearing. But I didn't find anything on how to calculate the bearing, before I start ...
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2answers
558 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 ...
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1answer
292 views

Haversine formula to calculate distance between real coordinates?

I need to calculate distance between two stations in a map in order to calculate empirical variogram in ordinary kriging to interpolate temperature data. Calculating distance in kriging using ...
2
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1answer
41 views

Need to get distance matrix for large set of points on-the-fly

I do not know much about GIS and I do not know much of the jargon. Hopefully you can help me a bit here because I am really unaware of the services and software available. My problem is as follows: ...
3
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1answer
180 views

Performing Point Distance analysis using Basic level license of ArcGIS for Desktop?

I am using ArcView Version 10.1 and I need to perform a point distance analysis like: What is the distance from A to B-Z, B to A-Z, C to A-Z, etc? What are the steps that I take to do this?
2
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1answer
2k views

How to calculate pixels per meter ratio, according to Google or Bing map zoom level?

I have an image and detect two points in the image. I want to calculate the distance between these two points. I'm using Google map and Bing map. I have x,y pixel values for both two points zoom ...
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5answers
8k views

How to cluster spatial data in R?

I am very new to R, so please bear with me : > I have bunch of data points with latitude and longitude. I want to use R to cluster them based on their distance. I have already taken a look at this ...
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1answer
19 views

How to calculate the shortest path to pass on 7.000 UTM points?

Anyone can give me an advice how to calculate the shortest path with a lot of UTM points? In total I have 7000 points, but it can be grouping 100 or 500. I have knowledges about Java and Python for ...
2
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1answer
207 views

How to calculate which zip code is closer to which in USA using C#?

I'm not living in USA, and I'm doing a small project for a company based in USA. The point is that, there are businesses and each of them have their address and zip code. Then, I have a form where ...
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1answer
26 views

Euclidean distance outside a Polygon (ArcMap)

I got some university coursework to analyse the best potential areas for a residential development project and I'm currently doing multi-criteria evaluation. One of the shapefiles in the dataset given ...
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2answers
101 views

Calculate distance between a set of points: lat and long in QGIS or R

I have shapefiles containing the location of several individuals along several months. Positions were documented with a 30 minutes interval. Tables contain the following data fields: collar (ID), ...
0
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1answer
36 views

Euclidean Distance between two lines

I have two lines in ArcMap 10.2.2 and was wondering if it is possible to create a raster showing the Euclidean Distance between them. Like to map each cell on one line to its nearest cell on the other ...
0
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0answers
50 views

Given distance (in meters) what is the angle in geographic reference systems? [duplicate]

In QGIS and other systems sometimes I have a layer in geographic reference system (typically WGS84, EPSG:4326) and I'd like to calculate a buffer of say 5000m around a point. So, given a point ...
5
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1answer
796 views

Calculating distance in WGS84 (MySQL and Geoserver)

Here is the environment in which I work: An application using geo-referenced data Database MySQL 5.5, storing georeferenced points A Geoserver server, connected to the MySQL database Here is the ...
4
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1answer
424 views

How can I make a Postgres/PostGIS ST_Distance_sphere query more efficient?

Within Postgres/PostGIS I have written an SQL query to get the closest distance for each element within a point coordinate table from a polyline table. The query comes back and works correctly, but ...
0
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1answer
21 views

'Find your nearest' type function with a large dataset

In a previous employment, I needed to display a "Distance to stockist" on our website. It would get your current co-ordinates (from a postcode or HTML5 geolocate) and then display a list of nearby ...
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2answers
35 views

Distance to, travel only on one surface

Looking to create a distance to wetland raster. However this travel distance must be through the water only. I have tried setting land to a high cost (e.g. 99) however doing so I have to set each ...
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0answers
40 views

Which projection should be chosen to model transmission lines across the USA?

I am looking at different options for high voltage power lines in the US. These power lines cross several states. Since in the end the distance is of importance, is the USA Contiguous Equidistant ...
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1answer
32 views

How do I interpret this proj4string and why doesn't changing units change its resuls?

I'm new to GIS - I have a background in statistics. I have the following proj4string: '+proj=lcc +lat_1=40.66666666666666 +lat_2=41.03333333333333 +lat_0=40.16666666666666 +lon_0=-74 +x_0=300000 ...
9
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1answer
288 views

Measuring distances between simultaneous points

I am working with GPS data and so I have UTM's with DATE/Time information. I have 2 groups of species (moose and wolves). I want to join the information from moose to wolves that match in time. So, ...
0
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2answers
33 views

Postgis: Query ST_DWithin in square instead of circle

The ST_DWithin query queries all geometries within a certain radius from another geometry (in my case a point). For performance optimization of my application I want to query in a square. So that the ...
2
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0answers
43 views

QGIS distance from point to line along a specific bearing

I've got a vector layer with points (representing customer locations) and another vector layer with a line (representing the coast line). I want to calculate a "smart" distance to coast. Specifically, ...
0
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2answers
397 views

Measure average distance between two lines with common endpoints

I have two shapefiles, each with a set of lines generated from start and end points. One shapefile has the straight lines generated from the XY To Line tool, while the other has lines generated from a ...
3
votes
3answers
1k views

How to measure minimum distance between objects in two layers using arcpy?

I am working on an alien species analysis looking at the spread of a species from the mainland to islands in an archipelago. I am doing the analysis using arcpy and I have succeeded in isolating risk ...
9
votes
1answer
1k views

Analysing movement using cost surfaces with ArcGIS Path Distance tool?

I would like to analyse hypothetical movement (on foot) in a landscape as based on energy expenditure, but I have run into some trouble that I am hoping that you could help me with. I have tried to do ...
1
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1answer
63 views

Cost Distance interpretation in ArcGIS 10.2

I am using the Cost Distance tool in ArcMap 10.2 to find the how far it is to walk to the closest area of green space along the road network in a town. I have a input raster of the location of the ...
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1answer
153 views

Zoom variable or pixel distance

I have query by distance working in a framework that generates a list of features within a fixed distance of a clicked feature. I would like to make the queried distance variable based on either: ...
2
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1answer
116 views

Geographic Heatmaps with Concentric Circles by Distance

I'm looking to generate a geographic heatmap (using 'ggmap') that overlays some dimension (to start, housing prices) over the lat/lon near a city center. Then I want to create circles of equi-distant ...
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0answers
60 views

Convert java.vividsolutions.jts.geom distance to meters

I am using com.vividsolutions.jts.geom to perform the distance calculations. I have a list of "LineString"s and a Point (Say A). I want to determine the The nearest LineString to the Point A. The ...
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0answers
23 views

Calculating position in SRTM grid

I'm actually trying to calculate a grid point position in a SRTM grid by row and column count. So I got a position by lat/lon, then calculating the row and column in my hgt-file (this post helped me) ...