The measure of separation between two entities or locations that may or may not be connected, such as two points.
12
votes
3answers
188 views
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. ...
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 ...
4
votes
1answer
171 views
Distance Matrix tool in QGIS. How to get result in metric? [closed]
I'm trying to calculate the distance between points in layer with distance matrix tool. And keep getting strange results no matter what. Like this
MASTER ------------SLAVE ---------------- DISTANCE ...
5
votes
5answers
439 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 ...
1
vote
0answers
19 views
How to perform a join on simultaneous spatial and attribute criteria in PostGIS [duplicate]
Possible Duplicate:
How to perform a join on simultaneous spatial and attribute criteria in ArcGIS?
I have two point layers and want to perform a spatial join on nearest distance.
I have a ...
0
votes
0answers
50 views
How accurate is spherical geodesic distance? [duplicate]
Possible Duplicate:
Approximating earth as sphere
We are in a situation where spherical distance computations may be more convenient and faster than ellipsoidal ones. However, I am ...
2
votes
1answer
140 views
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 ...
4
votes
1answer
358 views
OpenLayers measure tool - instant measurement
I need to use measure tool to measure distances (instant measurement!) in my application. Instant measurement example can be found here. But the main problem is that when I use instant measurement ...
2
votes
1answer
158 views
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 ...
4
votes
1answer
89 views
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 ...
7
votes
2answers
98 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 ...
1
vote
1answer
122 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?
5
votes
2answers
241 views
Dissolving polygons by attribute and in a certain distance (ArcGIS)
in a FeatureClass I have a lot of polygons which contain attributes of different landuse-types. Now I am trying to dissolve those polygons of the same landuse-type, but only if the distance between ...
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
0answers
150 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 ...
2
votes
3answers
334 views
How to measure minimum distance between objects in two layers using arcpy?
I am working on an alien species analysis looking at the spread of a species from the mainland to islands in an archipelago. I am doing the analysis using arcpy and I have succeeded in isolating risk ...
6
votes
1answer
328 views
Problem analysing movement using cost surfaces (involving ArcGIS's Path Distance-tool)
I would like to analyse hypothetical movement (on foot) in a landscape as based on energy expenditure, but I have run into some trouble that I am hoping that you could help me with. I have tried to do ...
1
vote
2answers
152 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 ...
1
vote
1answer
38 views
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. ...
1
vote
1answer
120 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 ...
3
votes
0answers
318 views
Performing a Multicriteria Analysis Using Distance Along a Road Network
There is the possibility that I will be working on a project which will look at thousands of properties in a region and measure their accessibility to different services (schools, parks, hospitals, ...
1
vote
2answers
186 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) ...
0
votes
0answers
48 views
Interpretation of MODIS VCF Data, concerning walking distance analysis
I'm still working on my diploma thesis (must be one of the last ones in germany..;)) which deals with distance analysis. I want to model walking distances and cost paths affected by slope, vegetation, ...
1
vote
1answer
236 views
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 ...
1
vote
1answer
686 views
How to get the shortest distances between features on separate polygon layers?
Suppose I have a county-level map for the state of North Carolina, U.S. Suppose I would like to compute the shortest distance of each county to any point along the border of Georgia. How would this ...
2
votes
1answer
207 views
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 ...
0
votes
1answer
97 views
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 ...
3
votes
1answer
187 views
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:
How to find the minimum edge to edge distance of polygons?
...
1
vote
1answer
204 views
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 ...
7
votes
5answers
797 views
Calculate distance in km to nearest points (given in lat/long) using ArcGIS
I have two point datasets in ArcGIS, both of which are given in WGS84 lat/lon co-ordinates and the points are spread across the whole world. I would like to find the nearest point in Dataset A to each ...
3
votes
2answers
2k views
How to calculate new point coordinates from distance and angle?
I want to calculate the coordinates of a new point.
What I have: The source point coordinates, the distance (meters) and the angle
For example: I want to create a point within 100 meters and 45 ...
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
0answers
80 views
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 ...
2
votes
1answer
76 views
How to Improve a Distance Model
I am working on a distance model that creates distance rings around a given point and assigns those rings a probability. The point is in the center of a 25 x 25 km area, and the model fails to assign ...
1
vote
0answers
23 views
Translate geographical coordinate [duplicate]
Possible Duplicate:
Calculating Lat/Lng X miles from point
I would like to know how could I translate a geographical coordinate to an specific distance. So for example let's suppose I'm ...
0
votes
0answers
258 views
Implementing custom (Vincenty/Haversine formula) functions for MySQL vs Using PostGIS?
I currently am using MySQL for all of my relational data. I have hit a crossroads with geo calculations. Since, MySQL does not have good support for spatial functions, I am contemplating on using ...
4
votes
1answer
912 views
Distance calculation : Integrating incremental gps data
I am trying to build a GPS based odometer based on android.
Currently , I am calculating incremental distance changes very frequently ( < 5 meter movement). The distance calculation in android is ...
2
votes
0answers
73 views
finding a location on a line using a point and a relative distance with arcgis js api
The problem I'm trying to solve is to find a point on a line given another point on the same line and a distance from the same point. I've been looking on the various RouteTask examples but they ...
2
votes
1answer
399 views
MySQL GeoSpatial function for ST_Distance_Spheroid? Metric used in return Type of GLength?
Is there a ST_Distance_Sphere, ST_Distance_Spheroid equivalent function in MySQL's GeoSpatial Support?
If not, any way to emulate this?
What is the metric used in return type of ...
6
votes
2answers
234 views
how to find the point in a country furthest from a boundary
i'm trying to find the point in south africa furthest from the sea or a landward boundary.
my method thus far:
i obtained a first guess at the centre of the inscribed circle and the three segments ...
7
votes
1answer
532 views
PostGIS - Calculate progressive distance between points on a GPX path
I am attempting to build an elevation profile using PostGIS-PostgreSQL only.
I have imported GPX data in my PostGis database, so now I have a table full of the GPS coordinates of the track and the ...
8
votes
2answers
676 views
Calculate Distance between a Polygon and a Point Along a Path
I am very new to ArcGis and am trying to figure out how to do this.
Basically, this is what I am trying to do:
I have a map of Canada and in it I have polygons representing areas (each about the ...
2
votes
1answer
2k views
Calculating the minimum distance between points and polygons in QGIS
I have two vector layers: one point and one polygon and I want to calculate the minimum distance of each point from the polygons (ie the distance from the closest point of the closest polygon). Is ...
5
votes
1answer
116 views
Projections appropriate for global analysis that preserve area and that preserve distance (but not necessarily in the same projection)
I am looking for a projection (or a set of projections) that decently preserve distances so that I can buffer every country in the world and have a similar level of minimal distortion for each.
I ...
4
votes
2answers
896 views
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 ...
3
votes
1answer
144 views
How to calculate maximum distance to an interpolated value along a contour in QGIS?
I'm planning to enter concentrations of groundwater contaminants collected from well locations into QGIS and then use interpolation functions to create contours of the groundwater plume. Can QGIS ...
1
vote
0answers
114 views
How to create a dynamic distance calculator for selected line feature classes?
My situation:
I am relatively new to GIS so forgive me if this is a stupid question. I am working on a project at a park that I am interning at where the goal is to create a single feature with ...
3
votes
2answers
1k views
How to find a point on given line that its distance from another point is given also?
I have this input:
(lat1,lon1), (lat2,lon2) - Two coordinates that create the line
(lat0, lat0) - Point on this line
d - distance
I want to find a point (lat, lon), where
(lat, lon) is on the ...
2
votes
0answers
414 views
Calculate cumulative distance between points in a dataset in ArcGIS 9.3 ArcInfo
I am working with several point datasets that I have received, with the points representing xy locations with elevation data for several levees in south Louisiana. I would like to be able to calculate ...
5
votes
1answer
254 views
How to compute the distance between centroids and polygons?
Suppose I have an Excel spreadsheet with the latitude and longitude of the centroid of every county in the U.S. I want to know the shortest distance from each county to any part of Oklahoma ...
