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

1
vote
2answers
202 views

How to show average walking distance to closest point in census tract in ArcMap?

Given a map layer of point locations, and a second map layer of census tract polygons for the same area, how would you create a map layer that shows the average walking distance to the closest point ...
-1
votes
1answer
67 views

Buffering algorithm [closed]

Does anyone know the algorithm of buffering? I had difficulty in drawing buffers. So I tried many values to acquire 1km buffer. I found value 0.008966 produces 1km buffer. Then I calculated inverse ...
8
votes
1answer
416 views

How do I calculate Manhattan distance with PostGIS?

I am using the ST_Distance function to calculate the distance between two geometries (a train station and a building) Since I know that all buildings and all train stations are in Chicago, which has ...
2
votes
0answers
36 views

Scale on map requires correction coefficient. But why? [duplicate]

I am computing the distance of a map I am getting from ArcGIS' REST services by using a calculator as provided by this answer. In a nutshell, it uses a GeodeticCalculator for distance computation ...
4
votes
0answers
271 views

How to calculate the average distance among set of points as measure of closeness

I have three series (or tables) of points in PostGIS which I want to compare. I would like to know how "close" each series is when compared to the other two. In other words I would need some measure ...
1
vote
0answers
63 views

How to set a defined distance between nodes to digitize in qgis?

Using QGIS (by now I have the 2.4 version) I would like to set some parameter (I don't know if such exists) that would impose a definite or maximal distance between nodes when digitizing a polyline or ...
1
vote
1answer
254 views

Distance Between Two Points vs Length of Linestring

So I have two points that I want to calculate the distance between. If I use: SELECT ST_Distance_Spheroid(point_a, point_b, 'SPHEROID["GRS 1980",6378137,298.257222101]') / 1000 FROM ( ...
1
vote
1answer
238 views

GeographyFromText and ST_SetSRID+ST_MakePoint different results?

Why am I getting different results? SELECT ST_DISTANCE( ST_GeographyFromText('SRID=4326;POINT(13.401111 52.383343)'), --berlin ST_GeographyFromText('SRID=4326;POINT(9.997559 53.533778)') ...
3
votes
2answers
288 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 ...
2
votes
0answers
137 views

GeoDjango order_by('distance') not working as expected?

Using GeoDjango, I am trying to sort a list of users based on the distance from a point. It does generate a list, but its not ordered by distance, though I specify that in my query. This is the query ...
2
votes
2answers
368 views

Calculating distances between consecutive points along rivers (polygon) using ArcGIS Desktop?

I have radio-tracking locations of semi-aquatic mammals. Now, I would like to calculate the distance between the consecutive locations using the river as the animals would swim (opposite to as the ...
1
vote
0answers
61 views

Calculate distance in point collection algorithm

I've got collection of points which are sorted by x,y and distance between n and n+1 (array of objects [{x:0,y:0},{x:1,y:1}....] I would like to calculate distance between all points (point 1 distance ...
2
votes
0answers
313 views

FME - calculating distance to points along a line

I am new to FME, and trying to get my head around what should be pretty straightforward issues, but I find myself going around in circles Basically I want to determine the distance (chainage) to a ...
3
votes
2answers
121 views

Determining closest representation of polygon as collection of points+radii

Have a bit of a tough question, which I realize there may not be an easy solution to. Figured what better place to ask. I'm attempting to transform a polygon into a series of arbitrary points with ...
0
votes
3answers
486 views

Calculate distance using 2 sets of lat/long values in the same record

I have a point layer with over 90K records in it. For each record I have lat/long field for incident, and lat/long for engine location. Is there a way to find the distance between Incident point and ...
6
votes
3answers
5k views

Splitting lines automatically at specific distances using ArcGIS Desktop?

I have a set of polylines which I need to split at varying distances from their starting points. In general, I'm looking for a something similar to the SPLIT function within the editor tool. There ...
1
vote
1answer
771 views

Calculating distance between two sets of Decimal Degree coordinates?

I have coordinates in decimal degrees e.g: point A:Lat,Lng(5.317101667,-2.023303333) and point B:lat,lng(5.317093333,-2.023318333). The altitude in Meters at Point A is 11m and the altitude and Point ...
0
votes
0answers
52 views

Devising measure of vertical distance from spring line?

I am building a model (using Logistic Regression) to explore the relation between a binary categorical dependent variable (parcels agricultural production quality) and several predictors, among which ...
3
votes
1answer
283 views

Distance from rivers, taking into account terrain elevation

I am interested in building a raster of the distance from rivers in a territory under study. I have digitized the course of the rivers in ArcGis 10.1. I have used the 'Euclidean Distance' tool to ...
4
votes
1answer
226 views

Calculate distance between point and linestring and how to represent that on QGIS?

I have loaded my data with osm2pgrouting and I have my network with ways (Linestring) and nodes (Point). The problem is : I have a database of doctors addresses (point) and I should calculate the ...
4
votes
1answer
268 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, ...
0
votes
2answers
454 views

Using grayed out distance/direction tool in ArcGIS for Desktop?

I have a set of five points (all with specific latitudes and longitudes) and I want to create a set of points which will be about 80 kms from the first set. I understand that I can use the ...
0
votes
1answer
128 views

Get CartoDB query by distance to work

Has anyone tried this tutorial: Query by distance ? This is a copy of the final code which they use for the map: <html> <head> <link rel="stylesheet" ...
1
vote
1answer
149 views

Calculating distance of polygons from coastline using ArcGIS for Desktop?

I have a series of polygons representing parcels of land. I would like to calculate the distance of each polygon from the coastline. I also have a polygon of the entire region of interest, i.e. an ...
1
vote
1answer
204 views

Distance Between Two Points Same Value Different Feature Classes

I have two point feature classes - one is the original data and one is the data after editing. I want to know how far each of the points moved in the editing process. How do I compare all of the ...
0
votes
1answer
3k views

I nead to find the nearest places based on latitude/longitude points

I have a java aplication backed by a mysql database which contains events with locations (latitude/longitude), the location data is saved as POINT data type. I nead to find the nearest events in some ...
1
vote
1answer
388 views

Calculated distance doesn't match Google Earth

I have a google earth route that measures 190.1km in Google Earth. I then pulled down the .kml file, extracted the points and measured them using Vincenty's formula (ellipsoid earth) and got 190.2. ...
1
vote
2answers
395 views

Calculating distances between points two feature datasets

I will do my best to explain my problem. I have two feature datasets. One set has about 100 points that are "city centers." The other dataset has points for each census tract in each of these 100 ...
0
votes
0answers
25 views

Asp code for distance in SQL sever

I've looked around but I can't find the answer anywhere and im getting kinda frustrated now. I'm using sql server and what im trying to do is to find apartments within a 0.5km radious of a said ...
1
vote
2answers
50 views

Spherical law of cosine what does the 'a' represent?

I want to use the spherical law of cosine formula, θ = atan2( sin Δλ ⋅ cos φ2 , cos φ1 ⋅ sin φ2 − sin φ1 ⋅ cos φ2 ⋅ cos Δλ ), to calculate distances between coordinates, but, I cannot for the life ...
0
votes
1answer
124 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
24 views

Find coordinate of point on the boundary of a circle given a latitude/longitude and radius [duplicate]

I understand how to use the haversine formula to compute the distance between two points on the earth. However, I would like to answer a similar, albeit different question. How can I compute the ...
1
vote
2answers
299 views

Calculating Distances between Field polygons via Road polygons using ArcGIS for Desktop?

I have two polygons layers, one (grey) is Roads, other (blue) is Fields. Can I calculate distances between Fields (by field unique ID number) using Roads layer as distance measurement? What tools or ...
1
vote
1answer
35 views

Is there a tool in arctoolbox for IDistanceOp.CostPathasPolyline?

Almost all the methods in IDistanceOp have a corresponding tool in the Distance Toolset Spatial Analyst Toolbox. However, I can't find anything in the toolbox for IDistanceOp.CostPathasPolyline. ...
0
votes
0answers
25 views

Find square with latitude and longitude for given lat and lng and distance [duplicate]

I have the coordinates of some point, lets say lat and lng, I want to find the latitude and longitude of top left and bottom right corners of the square, whose sides are located k kilometers from the ...
13
votes
5answers
18k views

Finding distance of point along polyline?

We need to find the distance of a series of point along a given polyline. We have a polyline dataset repsenting rivers in a catchment, broken up into river reaches (FID 1 through 35 for example). We ...
1
vote
1answer
498 views

Creating Longitude and Latitude Lines in Google Maps

I'm working on an independent high school project where i'm trying to build a simple differential equation model for diffusion. I'm trying to overlay the model on top of a map to visualize spread, so ...
0
votes
2answers
97 views

Joining two polygon layers based on distance?

I'm new to GIS so this question may be an obvious one. I have one polygon layer of urban land use and another polygon layer of swamps. How do I join the two layers so that I get a column in the ...
0
votes
0answers
26 views

avg distance within 2 geometry tables

I have 2 geometry tables: "f" with only one data and "s" with 100 data I want to find the avg distance of s to f these are the commands: CREATE TABLE f id int4 primary key not null , name ...
1
vote
1answer
57 views

How can I calculate the nearest distance to a landscape element taking the direction into account (i.e. slope direction, prevailing winds)?

I am trying to build a layer of distance to relevant landscape elements in a watershed. To be relevant, a landscape element must be downstream with respect to the runoff direction.  Clearly, I want ...
0
votes
0answers
2k views

Is there a way to calculate driving time/driving duration with google maps api without considering the traffic situation?

I am currently using this VBA-Code, written by Jamie Bull, to calculate both, driving distance, as well as driving duration, between approx. 1.500 villages and a specific shopping center, using excel. ...
1
vote
0answers
149 views

QGIS distance measure

using QGIS 2.2 and trying to figure out a way to obtain a distance measure for the width of pavement. I have 2 shapefiles: one of points which are at 5m intervals along the pavement centreline and ...
1
vote
0answers
172 views

Calculating closest distances in meters/kilometers given lat/long coordinates?

I am using ArcGIS 10.2 for Desktop. I have a shape file containing points worldwide with lat and long, and another world map polygon file whose Geographic Coordinate System is GCS_WGS_1984 and Datum ...
1
vote
1answer
28 views

nr of cells between cells

I want to do the following: I have a set of cells with the value 1, and a set of values with 2. I want to calculate for each cell [2] the distance - ideally number of cells - to the nearest cell 1. ...
1
vote
1answer
149 views

How to do point-to-point near analysis conditional on common attributes of the two layers in Arcgis 10.2 (advanced)

I am measuring the closest straight distance from cities of interest (in a layer) to their capital cities (in another layer). Basically, distance between a city and a capital city is calculated if ...
1
vote
3answers
593 views

How to determine Distance between points using ArcGIS for Desktop?

I am trying to figure out the distance between points based on 1000+ points using ArcMap 10.2. I have transit stops and am trying to figure out how far from stop 1 to stop 2, stop 2 to stop 3, stop ...
1
vote
0answers
44 views

How to determine distances of points from closest line? (Mapinfo or QGIS) [duplicate]

I have a set of points and a set of lines. I'd like to know distances of the points from the closest line... answering the question "how many points are within 500m to 1000m of one of the lines, how ...
1
vote
2answers
584 views

Find closest feature

How can I find the closest feature(coordinates) in a json file from a set lat lon using openlayers. Currently, I get the centroid point(lat,lon) from the selected polygon feature ok, but I Would also ...
9
votes
3answers
25k 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. ...
3
votes
3answers
605 views

Why is sum of st_length() of segments 20% too big?

I'm running a query to return the total length of some bike paths, from OpenStreetMap. Compared to the known actual length of these paths, they're all a bit too big - something like 10-30%. I know it ...