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

3
votes
2answers
44 views

Calculating areas outside a point

I have a university assignment that requires me to find an optimum location for a land fill site. There are various parameters I need to map. I have managed to map all the ones within a distance of ...
4
votes
1answer
291 views

Calculating Distances between coordinates

I have 75 coordinates in WGS84 that I brought in from an Excel table. They are now on my imagery basemap spanning across about a half mile on either side of a dirt road in Prescott National Forest in ...
6
votes
1answer
141 views

How to group 10k points into closest pairs?

I was first faced with a problem of grouping 1000 pairs into unique pairs to minimise the total distance - since this was a small number I solved it using linear optimisation: Part 1 - Basic/Naive ...
3
votes
1answer
67 views

Vincenty or (Project + Euclidean) for accurate distances

I posted a similar question on stackoverflow, however was directed here for more help. If my main goal was to calculate distances such that my error was minimised to the nearest metre assuming that ...
1
vote
1answer
33 views

QGIS: Distance Matrix tool omitting some points in output table. (qGIS 2.10.1-Pisa)

I have used the Analysis Tools -> Distance matrix to merge two datasets by the closest points. But in my output csv file, some of my points are left out. In the original datasets, none of these points ...
6
votes
3answers
737 views

Network distance computations using GRASS

I'm an ArcGIS user who's interested in learning to use GRASS. Can anyone point out resources that will help me in learning how to obtain network distances between (1) residential locations (points) ...
2
votes
1answer
541 views

Finding distance between consecutive points using ArcGIS Desktop?

I am wondering how I can get the distance between consecutive GPS locations in ArcMap 10 (i.e. the distance between consecutive GPS locations sent in during a wildlife telemetry study).
1
vote
2answers
288 views

Finding point on road network at specifc distance from a specific point

I have road network in a geodatabase. At a certain junction in network (Point A), I want to figure out Point B which is X kilometers away from Point A in certain direction. Summary: Point A: fixed ...
2
votes
0answers
69 views

Why this pyqgis code cause crash dump in QGIS?

In ArcGIS there is gp.EucDirection to calculate Euclidean allocation, distance, and direction around a point, Is there equivalent function in pyqgis or gdal? I wrote a script with help of gene and ...
1
vote
1answer
105 views

GeoDjango - save two Point fields, one for geography and one for geometry

Most of the explanations I've read for geography and geometry seem to suggest that one must only use either geometry or geography, and that the only way to use both is to cast/convert between one and ...
4
votes
2answers
605 views

Distance Calculation Output Does Not Identify Input Points?

I'm using ArcMap 10 to do distance calculations between a large set of points, using the point distance calculator. The output table generated gives me distances correctly, but the output categories ...
1
vote
1answer
88 views

Finding distance to closest road (polygon to line) in ArcGIS for Desktop?

For my project I need to find the distance to the nearest road from forest polygons. I'm trying to do a weighted overlay analysis (eventually) for a habitat selection project so I think I need to end ...
1
vote
2answers
485 views

Calculate the distance between two coordinates (WGS84) in ETRS89

I have an Excel-file with coordinates (WGS84). From these coordinates I create a line (shp) and transform it (ETRS89). After the transformation I calculate the distance from point to point. I do this ...
0
votes
1answer
81 views

Perpendicular Distance Markers on Polyline in MapInfo?

I have added chainage to a creek polyline in MapInfo v11.0.3 using the 1999 version of "Distance Marker" by Meridian. It looks poor as it does not have the functionality to create the markers ...
0
votes
0answers
48 views

How to create a shapefile from Excel file including coordinates of points and distances between them in ArcGIS?

I wanted to use network analyst in ArcGIS and I have coordinates of points in the network. However, I could not find a shapefile including road information between these points so far (length of links ...
3
votes
1answer
89 views

Getting point from known points to specific distance of polyline using ArcObjects?

I want to know the coordinates of a polyline from specific point and distance. I have attached image to clear the specification. say, I have a points B(2,3). I want to know the coordinates of A and C ...
3
votes
1answer
195 views

Finding distance within which set percentage of features fall using ArcGIS Desktop?

Is there a tool that tells how many features there are within a set distance in ArcView? asked about finding the number of features within a certain distance of another feature in ArcView. I have ...
0
votes
0answers
17 views

Scaling distance by area

For each administrative unit, I calculate the median distance between businesses. However, for larger unit, this distance is naturally bigger (and does not paints a fair picture of, say, the effort by ...
3
votes
3answers
724 views

Why is geography faster than geometry for distance calculations?

Intuitively, I thought geometry would be faster than geography distance calculations, but this says otherwise: http://stackoverflow.com/questions/3547699/need-performance-on-postgis-with-geodjango#...
6
votes
1answer
652 views

How can I make a PostGIS ST_Distance_sphere query more efficient?

Within PostgreSQL/PostGIS I have written a 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 ...
1
vote
1answer
41 views

Calculate point location with direction and range

I have a latitude and longitude coordinate pair and I want to find another point location (returning lat and long) but only have the angle/direction and distance from the first point. How can I find ...
1
vote
2answers
358 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 ...
2
votes
1answer
66 views

Measure shortest distance around polygon

How do I measure the shortest distance between two points (1 and 2) with respect to a polygon? So the shortest way around the polygon from 1 to 2.
1
vote
2answers
45 views

How to create for each point feature an Euclidian Distance raster in ArcGIS

I need some comment on how to create an Euclidian distance raster for a point dataset of about 100 features in ArcGIS. I need to create a raster for each single point. My question is, if there is a ...
1
vote
0answers
113 views

Google Maps Distance Matrix API - Queries per second?

I'm pretty familiar with Google's Distance Matrix API, but I'm unsure about one aspect of the Usage Limitations. The documentation states that you have access to 100 elements per query (element = ...
1
vote
1answer
33 views

Is it possible to use ArcGIS to define a boundary around a self-constructed 3D feature?

I am creating a 3D rendering of a future building and would like to know the distance from which this building would be visible from. Is it possible to use ArcGIS to define a boundary that delineates ...
3
votes
1answer
99 views

What is the real distance between positions?

I'm trying to figure out what gives me the most accurate distance between positions: Measuring distance directly (using Geod.inv)? Measuring distance in 2D (after transforming to a known projected ...
1
vote
1answer
73 views

GeoDjango and PostGIS distance query efficiency concerns [closed]

For example, if I want a query that says "show me all houses within 50km from here and order them from nearest to furthest", these are the questions and concerns I have: Assuming we are using EC2 (...
7
votes
2answers
130 views

Creating a point on edge of closest polygon

My project is looking at a grid in the ocean. I want to capture each ocean point's distance to the nearest coastline as a weight, and then use buffer to capture the sum of nightlight data within a 1 ...
1
vote
2answers
731 views

Distance between points along polyline ArcGIS for Desktop?

I'm using ArcGIS 10.3 (Desktop), and I'm trying to measure the distance between points following a path determined by a set of polylines. Hand measurement is not a viable option-- there are ~7500 ...
0
votes
0answers
100 views

Extend line to specific distance or a line

I want to extend my polyline to a given distance. How can I do this. I have attached image to clear my specification. I am using .net in ArcMap . I am also using python in the image, I want to ...
3
votes
1answer
158 views

Distance in meters between two geographic coordinates

I want to determine the distance in meters between two geographic coordinates. The points are: Lat (deg) Lon (deg) A: -33.3930906 -70.5452765 B: -33.3993212 -70.5468767 So if i calc the ...
0
votes
2answers
37 views

Points proximity to polygons in ArcGIS for Desktop?

I have a point feature class with 1725 records (spread out over NYC) and a polygon feature class with 13 records (also spread out over NYC). What tools or processes can I use to figure out what ...
4
votes
1answer
99 views

Buffer from Point or Polygon with Information from Raster

The intent of this work is to define a buffer around a point or polygon based on information from a raster. For instance if a polygon representing a city and the raster defines how long it takes to ...
0
votes
0answers
46 views

Select points greater than a certain distance from related points based on shared foreign key id

I have a PostGIS-enabled PostrgeSQL db, using QGIS, with data using EPSG:4326, and projected as EPSG:29903. I have a table with points with pk point_id and a table with images with fk point_id. I want ...
2
votes
2answers
141 views

How to calculate the distance to the nearest water source?

I have a polygon hydro layer of my study area and am trying to calculate the distance to nearest water bodies from my site. Since my site are 2km*2km grids I am not sure how to calculate it? Whether ...
2
votes
1answer
295 views

Calculate road distance between GPS points

I am working on tracking system that track location of vehicles on the map and tell their total distance from the beginning till today. I have device_id, timestamp and GPS location in the table like ...
4
votes
2answers
80 views

Get the 2 points immediately before and after a given point in PostGIS

In the picture below: The given point is C, I would like to select A and B, but not Z (which is closer to C than B but it's not immediately after in the LineString). Note that C is always ON the line ...
2
votes
2answers
96 views

ST_Distance loop

I want to create a postgresql function which calculates the distances between random points who are stored in one table. For the Table: CREATE TABLE s_1( id bigserial primary key, the_geom geometry, ...
3
votes
1answer
49 views

using a linear solver to get a “centre of gravity” of a set of points

As a programmer, if I have a linear solver available. How can I formulate the following problem as a set of constrains / decisions / goals for the linear solver? I have a matrix of say 10*10, so 100 ...
1
vote
0answers
100 views

How to calculate multiple distances between set of points and vector grid in PostGIS?

My set contains the following input data: A set of points and a hexagonal (vector) grid. For each cell in the grid, I want to calculate the driving-distance to each point. I thought this would be a ...
1
vote
1answer
74 views

Create a line from an array and measure its length with PostGIS (ST_MakeLine, ST_Length)

do I understand it correctly that it is possible to create a line out of an array with the function ST_MakeLine()? I would like to create a line from several points (more than two) and then calculate ...
4
votes
1answer
59 views

PostGIS point distance from polygon not 0 when on edge

I have a pretty simple problem: SELECT * FROM ST_Distance(ST_GeographyFromText('POLYGON((70 -40,70 -39,71 -39,71 -40,70 -40))'), ST_GeographyFromText('POINT(70.48 -39)'), False) returns 118....
3
votes
3answers
1k 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
votes
1answer
71 views

Divide line by length with QGIS [duplicate]

I'm a newbie using QGIS 2.12 and I'm trying to split a line in QGIS and place points every x meters. There is a tool in ArcGIS (divide by length add in). How to achieve this in QGIS?
0
votes
0answers
103 views

How to measure nearest neighbor in miles or kilometers between two point layers using QGIS?

I have tried to look for an answer to this question, but cannot find an adequate solution. I have two point layers. One is of locations by lat/longs of homes in Louisiana. The other is a layer of ...
1
vote
0answers
28 views

Measuring large distances when all layers are in decimal degrees using QGIS?

I just developed a distance matrix between various points across Canada in QGIS. The distances produced are in decimal degrees, and I would like to view them in metric. I am unsure how to do this.
1
vote
1answer
209 views

Find nearest road distance between two points for over 1000 points

I'm extremely new to QGIS and am learning the material on my own. I have two CSV files with latitudes and longitudes, one has school address information and the other has fast food restaurant ...
6
votes
1answer
800 views

Measuring Right of Way in ArcGIS Desktop?

I'm helping bring CAD people into ArcGIS so that everyone throughout the company is on the same page and there is one database for everything. Right now, one of the biggest hurdles is making sure all ...
2
votes
0answers
85 views

How to calculate shortest path from points in one layer to points in another layer via roads, in QGIS

I'm a new user of QGIS (and have experience using ArcGIS but zero programming skills) and I'm looking for a way to calculate the shortest path from addresses to subway stations via a network of roads. ...