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

learn more… | top users | synonyms

0
votes
1answer
109 views

Distance-direction computation of lines with exactly/more than two nodes?

A distance and direction tutorial provided as an Answer at How to add Direction and Distance to attribute table? uses: xat (0 ), xat (-1 ) and yat (0 ), yat (-1) for start and end points of lines; ...
1
vote
0answers
393 views

How to approximate point to segment distance on sphere?

I would like to approximate the distance of a line segment from a reference point on the map (coordinates are gives as lat/lon). In the Cartesian coordinate system I would simply find the closest ...
2
votes
1answer
194 views

GeoDjango: read geometry column in geography field

I have a Django application that needs to work with an existent PostGIS database, apart from its own database. I've configured multidatabase support, created a database router, created models for the ...
5
votes
1answer
881 views

calculate {minimal} distance between polygons in R

I have calculated the surface area of species distributions (merging polygons from shapefiles), but since this area can be comprised of quite distanced polygons, I would like to calculate some measure ...
0
votes
1answer
31 views

Determine when a route enters and leaves a polygon

I have all of the segments of a route from White Horse, YK to Miami, FL. Now I want to determine how many miles I travel in each State / Province. I have Polygons for each State and have been able ...
2
votes
1answer
234 views

using PostGIS to calculate distance of a route over a large area

I'm new to PostGIS and looking to measure the distance of the Pacific Crest Trail which spans western North America from Canada to Mexico. I have a data set containing the lat lon and dates from GPX ...
4
votes
2answers
2k views

What formula is used for distance between 2 points in Google Maps?

What formula is used by Google Maps for calculating the shortest distance between 2 points (having their Lat, Lng coordinates)? Is it purely based on Haversine? Or is it something different? Is there ...
1
vote
1answer
488 views

Calculate distance of points along a route QGIS

I have a line layer and a point layer, I need the distance between the first and the last point measured along the line. How can I do that using QGIS? Do I need to know linear reference? I don't ...
1
vote
1answer
703 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 ...
2
votes
1answer
952 views

ArcGIS giving measured distances and the scalebar incorrectly

I am currently using ArcGIS 10.1 and am struggling to be able to measure distance or set a scale bar correctly. Its currently giving me absurd results orders of magnitudes to small (0.5m etc). All my ...
1
vote
1answer
614 views

Creating Random Points in ArcGIS 10.1

I would like to create random points across my study area (which is a DEM raster) using the Feature Class> Create Random Points. However, I need to select/copy/move/delete these points and re-arrange ...
0
votes
0answers
130 views

Calculating distances between boundaries of polygons with Python

I have two sets of shape-files which have to be worked on within a Python Script. Those two Shape Files might differ from each other (same thematic content, but 2 different epochs). If there occurred ...
7
votes
1answer
855 views

What is difference between ST_DWithin and ST_Distance for proximity search in PostGIS?

I have records stored in a table with latitude/longitude coordinates stored in a geometry field. I want to find all records nearby a user supplied reference point. Note "nearby" probably means less ...
1
vote
2answers
2k views

Calculate distance in kilometers between two points

I have a few questions regarding the calculation of the distance between 2 postal codes. Take a look at the following code. ### # load the different packages we need ### require("rgdal") ...
-1
votes
1answer
195 views

Calculation of Euclidean Distance [closed]

What is the best way to calculate the euclidean distance between the elements of two point vector layers, without rasterising the layers? Thanks
0
votes
1answer
64 views

mile distance around each feature ArcGIS

I have a school layer information and a route map layer. In ArcMap, how can I show the x mile distance around each school base on route information. I did some research and I found different ...
0
votes
1answer
162 views

calculate least cost pathways for a region and create distance rasters to rivers [duplicate]

How do you calculate all the least cost pathways that exists for a region? I would like the output map to display all routes (and was wondering whether this can be done in one set of operations). I ...
3
votes
2answers
231 views

How to calculate the distance of sites to riverways

How do you calculate the distance of about 10 sites scattered across a region to bodies of water (rivers and lakes) using ArcGIS 10.1? I have the lat/lon coordinates of the 10 sites as a point ...
3
votes
1answer
31 views

Equidistant projection for northern Delaware

I'm just getting started on a long-term project involving northern Delaware. Most of my distances will use great circle distances from the lat/lon, but for a few applications I'll wind up using ...
5
votes
1answer
143 views

Optimize the locations of 2 additional restrooms on a trail (ArcGIS 10.2)

In the image below, the line is a trail and the point is an existing restroom. I would like to find the rough locations of 2 additional restrooms that minimize the maximum distance along trail from ...
3
votes
2answers
466 views

Variation of algorithms to find point from another point with bearing and distance

There are several algorithms to calculate distance between two latitude/longitude points. Haversine Hubeny Lambert-Andoyer Vincenty's formulae for inverse problem But there are not so many ...
0
votes
1answer
208 views

Manipulating distances in python. Problem with ShapeLength

I have a question more than a problem. I'm getting the distance of a line using python with arcpy.da.SearchCursor or FeatureClassToNumPyArray. The result I get is a double. Example: ...
2
votes
1answer
163 views

How to find least-cost paths including tunnels (where slopes are too steep)?

I'm currently working on a road path finding project for a motorway in ArcGIS 10. One criterion is obviously the slope angle. What I would like to do is to create a new cost surface which finds ...
2
votes
0answers
75 views

coordinate system for calculating distance at the nation scale

I want to use ArcGIS 10.1 to calculate the straight (euclidean) distances from zip codes to their nearest city centers in about 300 U.S. metropolitan areas. I have two point shpfiles: one includes the ...
2
votes
1answer
712 views

PostGIS: Calculate the length of just the portion of linestring that intersect with a polygon

I want to calculate the portion of the linestring that lies within the limits of a polygon. Better with an image What is the length of the portion of linestring within Province A? and within ...
3
votes
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 ...
4
votes
2answers
408 views

How to calculate the azimuth of a line of a multilinestring in PostGIS?

I have two spatially enabled tables in PostgreSQL with a geometry in each: First table is with POINT type, second is with MULTILINESTRING. I need to calculate the azimuth of the LINESTRING part of a ...
4
votes
1answer
223 views

MMqgis (hub distance) error in distance

So I am trying to calculate the distance of several points to a coastline, using hub distance (mmqgis plugin) in Qgis Dufour 2.01. I am using the default coordinate system (WGS84) and I, already, ...
1
vote
4answers
2k views

Return all results within a 30km radius of a specific lat/long point?

I have a table with a column the_geom which contains data similar to: ...
3
votes
2answers
206 views

Calculate distance in QGIS, wrong geographic projection?

I'm trying to do the following: I have 2 shapefiles, one containing all the public schools in NY, another one containing the hotspots in NY (both in points form). Now what I'm trying to do is ...
0
votes
2answers
545 views

Find longitude for point between two coordinates with pyproj?

I've written a function to get the longitude of a point of known latitude between two known points (might not be working correctly yet), but I feel like there must be a better way of using pyproj to ...
3
votes
3answers
525 views

QGIS spatial join, calculating distance from polygon to point layer

I am trying to perform a kind of 'spatial join' in Arcgis, joining to a polygon layer atributes of the closest feature of a point layer, as well as distance. But 'spatial query' doesn't offer an ...
2
votes
1answer
99 views

Road Miles Calculation without Google Maps

We have two ZIP codes we want to calculate the road mile difference. Google maps states you cannot use their API if you do not show a map. Is there another service that provides this type of ...
0
votes
1answer
82 views

QGIS proximity raster with extent beyond original coverage?

I need a raster coverage of distances from points outside the geographic region of interest, and am having trouble doing this with QGIS. Questions like this one (Calculating distance to points in ...
3
votes
3answers
1k views

How can I calculate the distances between my points in sequence automatically?

I have a rookie problem (again). I am trying to measure distances between points and writing the calculated measure between these points in the attribute table. The points represents a vehicle's ...
0
votes
1answer
53 views

Can distance be calculated to a destination feature based on an attribute in the source?

All, Is it possible to specify which destination point to calculate distance to based on an attribute in the source? STDistance will give me the distance each student (point) is to their closest ...
3
votes
0answers
198 views

converting a distance to a map distance

I have a point and a polyline. I need to find the perpendicular distance between each segment of the polyline and the point. By each segemnt of the polyline I mean that, each polyline may contain more ...
1
vote
1answer
138 views

Distance between two latitudes [duplicate]

I need to know the distance in feet between the coordinates N34-00.000 and N34-00.001 (Degrees, minutes and thousanths of minutes) I computed approx 6 feet but am not confidant in my math skills.
4
votes
1answer
480 views

Calculate distance to median point for a group of points in ArcGIS 10.1

I have a shapefile called "household_points" of ~2,000 points, which are divided into about 100 sites. The shapefile has a field in the attribute table called "SNAME" and in the field each point is ...
2
votes
0answers
67 views

Get distance after path distance allocation

I use ArcGIS 10.1 in Windows XP. I have a two point feature data sets One containing a single point P1 and another containing multiple points Pm. I computed the minimum-distance path from P1 to each ...
1
vote
2answers
588 views

Calculating millions of distances with Road Graph

I'm new to GIS but thanks to the answers I got in another question here on GIS stack exchange I was able to increase my knowledge significantly. This question is related to an earlier question I asked ...
8
votes
3answers
597 views

New to ArcGIS and want to compute distance between two points “as the fish swims”

We have a layer named Hydrography which is the water area for a given assignment. I have a station point and a target point. I need to compute the distance between those two points but inside of the ...
6
votes
1answer
2k views

Shortest distance from point to line (big dataset)

What is the best method to calculate the distance from the nearest road for a series of address points in QGIS, having a very big dataset? (QGIS 2.0.1, Win XP) I read the answers to previous similar ...
0
votes
1answer
95 views

Shortest path to nearest… something

I have a list of addresses and a map including train stations, schools etc., and I would like to calculate the shortest distance from each address to the nearest train station, school etc. I'm aware ...
3
votes
2answers
420 views

How to calculate distances between addresses and cities and coast line?

I am totally new to GIS, and so I apologize if my question is not clear enough. My basic problem is the following: I have about 160,000 Danish addresses with longitude and latitude for each address. ...
1
vote
1answer
1k views

Measuring Distance from Point to Point Along a Path in ArcMap

I am looking at a village and want to find the distance from each house (point) to the pagoda (point). However, I want the distance to be measured along a path (which I digitized as a polyline) and ...
0
votes
1answer
1k views

SQL to get points within a certain distance

I am new to using spatial data types in sql server. I have managed to create a column of Approx 50,0000 geometry points (from x,y data) and would like to find out which (count number of) points are ...
5
votes
3answers
177 views

What is the precise distance from equator to pole according to WGS84?

For calculating areas of polygons by means of projecting to a cylindrical equal area projection I came across the following discrepancy: I ended up with a different distance, off by more than 5km, ...
1
vote
2answers
165 views

Distance between latlongs varies in different projection systems?

I have shapefiles with correct projections. The SRS is EPSG 32735 (WGS 1984 UTM 35S) Now, I have these two coordinates from this projection system: (31.3751,-23.4388) and (31.3779,-23.4355). ...
1
vote
1answer
375 views

Mimimum distance between points (Postgres/PostGIS)

I have a table (tab_Cities with cities which own more than 50000 inhabitants. The table also contains lat, long and the_geom as columns. I can already see the points via QGIS. Now I want to write a ...