# Questions tagged [distance]

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

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### find latlngs that are some x distance away from a point to south to north to east to west

I have a latlng i want to find four points with equal distance from this latlangs in all directions east, west, south an north is there any formula . I am trying to build polygons around higways so ...
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### How to generate a point distance matrix using shortest network distance? [closed]

My problem is as follows. To start with, I have the following spatial datasets: A road network; 13,000 odd point locations representing populated localities (ie places where people live); Service (...
217 views

### How to calculate average distance from points to points?

I have a point layer of 400,000 voter residencies and a point layer of 500 polling places. I am trying to find the average distance it takes voters to get to their polling location. Distance by road ...
771 views

### calculate total Miles in a polygon using Google Map

I have an application that allows the users to create any custom polygon layer on top of google maps, i am interested to know if their is a way to select the road layer in this polygon and then ...
77 views

### windows function with points in a mixed (multipoint/point) table

I have a table comprising multipoints (tracks) and points (stops between tracks). there can be several consecutive multipoints. now, i want to merge any points lying very closely to each other (...
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### Python - OGR: Distance different than in ArcGIS

I want to determine the shortest distance between a point and a line. I use the following Python script to do so. If I compare the result of the script with the result of ArcMap's Near Analysis, I get ...
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### Distance between DB field and Point using PostGIS

I'm using Postgresql 9.0 with PostGIS 2.0 extension. I've got the table and geographic field location: =# SELECT * FROM geography_columns; f_table_catalog | f_table_schema | f_table_name | ...
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### ST_Distance is not delivering right results

I want to calculate the distance between lat/lon points. I tried the following queries: Select ST_DISTANCE(ST_GeomFromText('POINT(-73.97923 40.75571)', 4326), ST_GeomFromText('POINT(-73.974509 40....
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### How to create a point along a line given a distance from another point

I'm trying to figure out a point(D) on B-C that is a specific distance from A. I really don't have any idea on how to proceed with the ellipsoidal math so I figured I'd ask here. How would I figure ...
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### Does IDistanceOP.EucDistanceFull require a projected coordinate system?

I have designed an implementation of ArcObjects' IDistanceOP.EucDistanceFull. It takes its input as a feature class and converts it to a GeoDataset with which EucDistanceFull can work with. It works ...
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### Get the total distance from a point to the end of a linestring

I have a list of GPS coordinates that make up a bus route: busRoute = [(x1, y1), (x2, y2), ... (xn, yn)] I also have a point that may not be exactly on that route (due to GPS error): ...
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### postgis distance calculation between points with lat, long coordinates

Team, I am new to postgis, but a postgres user for quite a while. I would like to compare the geospatial capabilities between postgresql and mongodb. I have the lat.lon, zip code of US locations; ...
391 views

### What is the preferable value for setting tolerance for selecting a feature

I know it's really a basic question. But I am really confused about this. For selecting a point feature by mouse click, we need to set a tolerance value to create the envelope. And here is the problem ...
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### What formula does SQL Server 2008 use in STDistance?

I am analyzing the accuracy of the STDistance function for geographical objects in SQL Server 2008, in order to understand its behaviour better I need to find the underlying formula. Does anyone ...
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### error in estimate distance?

i do some experiment place two sensor node between them 4 meter as distance. then i get these GPS information: node1: Latitude: 32, 33.255 , Longitude: 36, 0.6632 node2: Latitude: 32, 33.228 , ...
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### Pivot a polyline at vertex or distance using ArcObjects C#

I hope you can help me with that one. I'm using ArcObjects with C# trying to rotate only one part of a polyline at a vertex or distance along the polyline. The polyline is zAware and has values at ...
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### Accurate and fast nearest neighbour, which distance function should I use and how to it speed up? [duplicate]

I am solving the following problem: I have a map with many points in it and I need to find the nearest point to given location. Each point carries information about it's latitude and longitude. This ...
435 views

### Offset a Polygon defined in Lat Lng points by a given distance of miles or km

I am trying apply a positive offset/buffer (enlarge a shape equally from the borders) to a polygon that is made up of a series of latitude/longitude coordinates by a distance that is defined in either ...
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### API for time and distance between two addresses?

The Google TOS appears to limit the use of API for time and distance between two addresses to use in conjunction with a displayed map. Does anyone know of any other mapping data source that offers a ...
974 views

### Correct coordinate systems, but trustworthy distance between points?

I have limited GIS experience with projections and I have some questions about trying to accurately display point data from two different sources in ArcGIS 10.1 in order to do a proximity analysis. ...
812 views

### Get the distance between 2 WGS84 GEOSGeometries

I currently want to check if 2 given GEOSGeometry objects of type Point are within 100m of each other. (length flexible) Looking at previous asked questions on this topic, most of the answers were ...
596 views

### Rasterize vector with gdal

"I would like to calculate the Euclidian distance from a residence to a public service of interest e.g. the distance from a residence to a green space (as the crow flies) in QGIS. After browsing the ...
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### QGIS, Euclidean distance analysis [duplicate]

i wanna generate euclodian distance map for my road data. I 'll use it for multi criteria analysis. I can get it by using Arcgis Euclodian Distance tool but i wanna generate it in QGIS environment. I ...
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### tool to find the routing distance between two latitude/longitude points using OSM data

I need a tool to find the distance between two points whose longitude and latitude are given. I am making an application so it will require bulk queries, so i cannot use google maps distance matrix ...
88 views

### Allocate places according to distance

I've asked this over on Stack Overflow but thought that someone may have a GI point of view that may help: As an over-simplified example I have a list of events that have a maximum attendance: ...
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### Calculate distance between X/Y coordinates by individual in R

In R, I'd like to calculate the straight-line distance between each capture of an animal in my dataset - no need to take into account the curvature of the earth. I have a dataset that looks like this:...
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### Calculate the distance between two contours

I have two contour polylines (single shapefile) and I would like to calculate the mean, min and max distances between the two lines. Is there a function in ArcMap 10 (ArcInfo license, incl. Spatial ...
1k views

### Distance Matrix in QGIS

Can anyone help me with the distance matrix tool in QGIS? Is there a tutorial about it? It sometimes crashes when I use it and the values that it produces seem strange. I am a beginner in QGIS, so I ...
1k views

### Calculate 'Rectangle' Coordinates Given 2 Points and width [closed]

I want to create a rectangular polygon using two points as guides. So let's say a journey starts in Egypt and ends in London, my polygon should have 4 points: 10 miles further from London than Egypt ...
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### How to Determine to world map size in pixel given this data?

How to Determine the world map size in pixels given this data? Map size of a particular area say, for example: Makati city, Philippines with bounds: Top-Right: 121.0281, 14.56497 Bottom-Left: 121....
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### How can I represent distance using the dashes or markers of a vector line?

I am a very basic user and dont know the lingo to get to the gist of my question so some background might help. Ive volunteered to create a pre-incident planning system for my rural fire department. ...
685 views

### How do I get the upstream distance to all points in a DEM from a single downstream point?

I want to get the upstream distance to all points in a DEM from a single downstream point. The goal is to create a "downstream distance to a point grid". This then would allow me to create "distance" ...
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### How to draw a polygon with preset length in OpenLayers?

For a project I am working on, I need to be able to put a polygon on a map using OpenLayers, based on a variable point that can be set by a user. The polygon is an isosceles triangle of which two legs ...
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### Getting points within a range from a postgres database?

ok so this is query i'm making which returns no result: SELECT building.gid FROM building WHERE ST_Dwithin(building.geom, ST_GeomFromText('POINT(long lat)',4326), 400) If I run this in ...
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### Tunnel distance approximation

Having two points (longitude, latitude) on earth, if I am sure their distance is under 100 km; how much error will I have using tunnel distance approximation? (Defined at here) Note: Currently I am ...
370 views

### Which SRS to use for global distance queries?

I have a database with a lot of points in WGS84. Now I am building an cache that performs NN and points in range queries using a KDtree. The point [sic] is that the search radius will be provided in ...
633 views

### Calulate distance between two points [closed]

If I have two coordinate points of (lat, lon), how would I calculate the distance between the two?
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### Looking for a fast, open-source raster cost-distance function to use in code

I've been scouring the internet for a fast, open-source cost-distance function that I can embed inside my code. The functionality should basically work like the ArcGIS implementation where I can ...
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### USA Contiguous Albers Equal Area Conic

How do you convert from USA Contiguous Albers Equal Area Conic to meters? Or, to latitude and longitude? I am using ArcGIS 10.1, and within it, ArcMap. The shapefile I have reports the coordinates ...
931 views

### Recovering Latitude and Longitude from Albers to Compute Distance

I have a shapefile of U.S. counties in USA Contiguous Albers Equal Area Conic. I want to do distance calculations. For example, distances from one county to another. I do not know how to interpret ...
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### Obtaining coordinates when computing distance of a polygon to a line

I have a shapefile of a county. I am interested in computing its distance to a line, which I've been doing using Near. I want to know the coordinates on the line that produces the minimum distance. ...
263 views

### Distance of many polygons to a segmented line

I have a shapefile of U.S. counties. I also have a line segment. I want to compute the distance of each county to the line. I have also divided the line segment into 10 equal segments. I want to ...
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### How to find the closest Edge from a Line

Currently I'm working on a basic 3D model viewer in MATLAB, which can import .OBJ files (modeled in e.g. Blender). The purpose of this viewer is to test different subdivision schemes (like Catmull-...
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### If the Earth was flat, what unit of measurement would distances between geographic points be represented as?

A whole lot of abstraction- given two longitude/latitude points given from a GPS, I'm using the Pythagorean distance formula to find the distance between them. What unit of length would the distance ...
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### How to perform trilateration using 3 lat/lon points without distances? [closed]

I read this thread Trilateration using 3 latitude and longitude points, and 3 distances explaining about trilateration using 3 latitude and longitude with measured distance. The problem is I want to ...
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### How to make a minimal distance matrix for polygons using QGIS?

I have a set of polygons and I want to find minimal distances between the edge of each pair of them. It's similar task as in this question: Finding minimum edge to edge distance of polygons using ...
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### PgRouting Driving Distance crashing postgis server

I haven't used PgRouting much so I'm a little in the dark here. However, I am attempting a driving distance calculation like the one described by Underdark here. My SQL is identical, I have a ...
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### Is there a ModestMaps or other flex library for finding the distance between 2 lat/lon coordinates?

I'm using ModestMaps in my Adobe Flex application. Is there a flex library method to calculate the distance between two of my lat/lon coordinates, or am I stuck coding the Haversine by hand? I've ...