The measure of separation between two entities or locations that may or may not be connected, such as two points.
7
votes
2answers
143 views
How do I group near points with GPS positions?
I'm an IT person so I don't know too much about projections and so on, I hope you can help me.
I have made an application for Android that collects a GPS position, so I have the latitude and the ...
2
votes
1answer
74 views
Find projection of a point to a line
I have a segment defined by 2 LatLon points(A and B) and a third LatLon point (C).
I need an alghorithm, formulae, or some code to find the projection point of C on the segment AB (call this point D) ...
0
votes
1answer
23 views
Point to point distance over specified distance
I need to calculate the distance between neighbouring points which conform to a staggered line.
I have two point datasets, one being the baseline and another the monitor. The points typically reside ...
4
votes
5answers
7k views
For every point, distance to nearest polygon of type X?
In ArcGIS how might one calculate as an attribute value the distance to the nearest polygon of type X? Say we have a point layer of wildlife observations and we want to know how far each of them is ...
2
votes
1answer
55 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 ...
5
votes
1answer
260 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 ...
-2
votes
1answer
66 views
How to find length of transmission line for all possible configurations between 9 villages?
My dissertation is on designing transmission line using ArcGIS between 9 villages of Uttarakhand.
How can I find the length of transmission line for all possible configurations between all the ...
0
votes
2answers
58 views
Average distance from points to line
I have a polyline road dataset and a study area (polygon) covering the the road dataset. I want to determine the average distance for every given point within the study area to the nearest road. i ...
4
votes
1answer
49 views
How to find the Closest Facility (euclidean distance)?
I have some facilities and incidents, and I want to find the closest facility for each incident. I've done it via Network Analyst (with a network dataset) but I'm wondering if you can do it with just ...
3
votes
1answer
94 views
How to measure the distance of multiple points to a line
I have two shapfile in QGIS to which I am trying to find the distances between. I have a shoreline which is a vector line and then I have hundreds of data points in the ocean. What I am trying to find ...
3
votes
1answer
25 views
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 ...
0
votes
0answers
42 views
how to create Euclidean Distance in QGIS
I'm trying to create distance layer for points in QGIS (similar to Euclidean Distance in ArcGIS).
I see the answer you give in the url
Calculating distance to points in QGIS
I try it using rasterize. ...
0
votes
0answers
17 views
Can I apply the Euclidean Distance tool for a single point feature class? [duplicate]
So, as suggested in my previous question, I tried to perform perform the Euclidean Distance tool for a single point feature class. For som e reason it doesn't work and the error given is ERROR010092: ...
2
votes
1answer
47 views
Create raster distance around a single point feature class
Okay, so I'm relatively new to ArcMap and I'm trying to use the Fuzzy membership for suitability test. I have a single point feature class that I wanna use for this analysis. I know that in order to ...
2
votes
1answer
60 views
How to access the road graph plugin in python?
I am developing a few scripts in Python for QGIS 1.8 to automate some geo-tasks and one of them would be to calculate the shortest distance from a hospital to each building in a town.
I would like to ...
14
votes
3answers
2k views
How do I find the distance between two coordinates in an ellipsoid?
Lets say I have two sets of latitude and longitude. How do I find the distance between the two locations if I assume the earth is a perfect ellipsoid (with an eccentricity of 0.0167)?
5
votes
5answers
438 views
How to calculate distances in a point sequence?
I'm looking for help calculating the distance between a sequence of points that are in a single Shapefile in QGIS. Below is what my data look like and a blank distance column I've added to show how ...
0
votes
1answer
42 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 ...
4
votes
3answers
340 views
How to efficiently find points within an elliptical area?
Using PostGIS 2.0.0 I need to filter the results of a function, which returns many POINTs, to find the ones that lie within an elliptical area defined by two points and a distance (all parameters ...
3
votes
1answer
52 views
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):
...
1
vote
1answer
126 views
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;
...
1
vote
1answer
50 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 ...
15
votes
3answers
5k views
Why is law of cosines more preferable than haversine when calculating distance between two latitude-longitude points?
In fact, when Sinnott published the
haversine formula, computational
precision was limited. Nowadays,
JavaScript (and most modern computers
& languages) use IEEE 754 64-bit
...
3
votes
1answer
59 views
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 ...
12
votes
2answers
188 views
What is the approximate error of the Pythagorean Theorem vs. Haversine Formula in measuring distances on a sphere at various scales?
Many people when first trying to calculate distances between two longitude / latitude pairs ask if Pythagorean theorem works as an appropriate distance function.
Most often people answer "no, the ...
0
votes
1answer
40 views
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 , ...
3
votes
1answer
125 views
Create points at shortest euclidean distance to other points
So, I have a lot of points, and I need to site three new points so they will be at the shortest euclidean distance between all of the other points.
In other words, these three new points that I need ...
3
votes
1answer
119 views
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 ...
2
votes
1answer
1k views
Find points within a distance using MySQL
I have a mySQL table with user name, latitude and longitude of the user. I would like to get a list of user who are inside the circle or square of a given latitude and longitude with given distance. ...
1
vote
1answer
96 views
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 ...
0
votes
0answers
41 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 ...
6
votes
4answers
220 views
How to calculate the “depth” of a linestring using postgis
I have linestring features, which look like bent linestrings, hemicycles or convex or concave linestrings. In the moment I can select the distance between the startpoint and endpoint of each feature. ...
4
votes
1answer
88 views
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 ...
2
votes
1answer
96 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.
...
0
votes
0answers
16 views
Distance from rivers-Zonal Statistics [duplicate]
I am using arcgis 10.1
I am trying to calculate euclidean distance from each feature using this large rivers shapefile http://www.arcgis.com/home/item.html?id=44e8358cf83a4b43bc863646cd695945 .
And ...
0
votes
1answer
91 views
Why is pgrouting driving distance skipping edges?
I have a road network where I do a driving distance operation through pgrouting. This is my SQL:
SELECT * FROM driving_distance('SELECT gid AS id,source,target, cost FROM ...
8
votes
1answer
111 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, ...
1
vote
1answer
122 views
Get the distance from a point on a polyline to polyline's from point
I have a polyline and a point on the polyline. I need to find the distance from the from point of the polyline to that point.
ICurve.QueryPoint method does the opposite thing. It gives a point ...
2
votes
1answer
109 views
Trilateration 3D - Vincenty's Formula
with reference to Trilateration using 3 latitude and longitude points, and 3 distances.
The accepted answer was votes as shown in wikipedia at: http://en.wikipedia.org/wiki/Trilateration in ...
15
votes
5answers
5k views
Trilateration using 3 latitude and longitude points, and 3 distances
I want to find out an unknown target location (latitude and longitude co-ordinates). There are 3 known points (latitude and longitude co-ordinate pairs) and for each point a distance in kilometers to ...
0
votes
0answers
69 views
How to calculate new coordinates by given distance, angle and altitude
I'm using C function to calculate new coordinates by given distance and angle to download google static maps tile by tile to create small map at given zoom. I have troubles because this code works ...
4
votes
1answer
75 views
Distance from waterways
I have an sdc file with water bodies, i.e. oceans-rivers-lakes. I want to combine it with a shapefile with the boundaries of countries all over the world and produce two measures: 1) The average ...
0
votes
2answers
107 views
Road network Analysis
I have a Road layer and Point features of some Bus stops from the same area.I want find the Road distance between the Bus stop.Please help me find it.
I have QGIS,ArcGIS,and FME.
Thanks,
RKM
1
vote
0answers
110 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 ...
2
votes
2answers
91 views
Calculating the distance from each point in one layer to the nearest point in another layer
I am trying to find the average distance from several points in a layer to points in another layer. I am using ArcMap Basic - I know there is a way to do this using the Advanced version of ArcMap but ...
3
votes
2answers
142 views
Converting lat lon into co-ordinates (in ft of m)
I have a set of latitude and longitude of a series of points which specific the trajectory of a vehicle.
If I consider the first point as the origin (0,0), is it possible to convert the trajectory ...
2
votes
2answers
118 views
Calculating the distance between points and multiple lines
I have a point shapefile of about 100 points and a polyline shapefile of about 200 lines and I am interested in finding the distance between every point and each individual polyline. My polyline ...
3
votes
1answer
75 views
GDAL 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 ...
1
vote
1answer
148 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 ...
0
votes
1answer
99 views
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 ...
