Linked Questions

1 vote
1 answer

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.
Sarah Good's user avatar
0 votes
2 answers

Getting a "square" of lat/lon for database query [duplicate]

So I want to get the square formed by a single point of lat/lons, my plan was to take that point's latitude, divide by 360, and multiply by the circumference of earth. Giving us the distance from the ...
OneChillDude's user avatar
22 votes
5 answers

What is unit of Shapely length attribute?

I'm doing a very simple calculation of the length of a Polyline using shapely: from shapely.geometry import LineString ... xy_list = [map(float, e) for e in xy_intm] line = LineString(xy_list) s = '%...
LarsVegas's user avatar
  • 2,556
20 votes
3 answers

Algorithm to find nearest point

I have a list of a few hundred cities with their latitude/longitude. Given another location (also in lat/long) I need to find the nearest city. As I don't use any GIS, by now the obvious algorithm is ...
lujop's user avatar
  • 365
9 votes
5 answers

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 I'...
Kerrie's user avatar
  • 91
12 votes
3 answers

What is the right solution (and map projection) to compute distances between points located all over the World?

After my study on map projection I realized that it is very difficult to choose a projection that allows to compute simultaneously the distances between a great deal of points if these points are ...
e-falcon's user avatar
  • 123
8 votes
3 answers

Which is the most accurate method of measuring distance?

I aim to analyse the accuracy of the various methods of geodesic calculations (distance between two points on Earth)based on the three assumed models of Earth - flat, spherical & ellipsoidal. I ...
Yathannsh Kulshrestha's user avatar
4 votes
5 answers

Approx distance between any 2 longitudes at a given latitude

Given a SINGLE longitude coordinate in decimal degrees, how do I calculate the distance in miles or km between latitude 0 and 1 at that longitude? ie what is the formula? For example, given 51.43567 ...
dewd's user avatar
  • 177
7 votes
2 answers

Find tangent point on circle furthest east or west

There are few ways of articulating my question. It starts with a known circle on a sphere, i.e. a point-radius, and one that does not cover a pole. I would like to calculate the point furthest west ...
David Smiley's user avatar
3 votes
3 answers

Why is this polygon "self intersected" and invalid?

I have a polygon defined as follows: segment from 43:29:02 N 003:50:39 E to 43:34:12 N 003:43:04 E arc(CW): center (43:34:49 N 003:58:16 E) from 43:34:12 N 003:43:04 E to 43:45:45 N 003:59:56 E ...
Marc's user avatar
  • 317
6 votes
1 answer

What kind of margin of error can I expect in figuring distance?

I have reviewed Why is law of cosines more preferable than haversine when calculating distance between two latitude-longitude points? and that does not equate to the specific question that I wish to ...
Tango's user avatar
  • 169
1 vote
2 answers

Generate random location within specified distance of a given point

In a simulation (not using any GIS), I need to generate a random location that is within a specified distance of a given location. I found a very helpful post here on this exact topic: How to ...
jetset's user avatar
  • 111
5 votes
2 answers

What is a delta in lat/lon called?

What is the delta between two lat/lon pairs called? Delta degrees? Arcs? Is it some quantity of distance but what is its unit of measurement? And related: Can we use pythagoras to calculate this ...
RickyA's user avatar
  • 353
2 votes
1 answer

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 ...
user30446's user avatar
4 votes
1 answer

JTS - Java Topology Suite - Calculate radius from a given point

From point A, I want to check if a point B is within a certain radius from A. How calculate it usindo JTS? I tried this: Coordinate posicaoAtual = new Coordinate(-12.974900375893823, -38....
Luciano Borges's user avatar

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