5
votes
3answers
140 views

What is the precise distance from equator to pole according to WGS84?

For calculating areas of polygons by means of projecting to a cylindrical equal area projection I came across the following discrepancy: I ended up with a different distance, off by more than 5km, ...
3
votes
1answer
323 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) ...
1
vote
0answers
334 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 ...
5
votes
2answers
5k 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 ...
4
votes
1answer
1k views

Distances in {Plate Carrée projection - EPSG:4326 - WGS84}

So, "4326 is just the EPSG identifier of WGS84" [3], indeed http://spatialreference.org/ref/epsg/4326/html/ says it is a GEOGraphic Coordinate System: GEOGCS["WGS 84", DATUM["WGS_1984", ...
19
votes
2answers
414 views

Precision when working with spatial data in GIS

Is there a basic or introductory study that examines and compares the precision of spatial data when working with varying precison of the data input, like having 1, 2, ... decimal places? with the ...
9
votes
4answers
8k views

How do I calculate the bounding box for given a distance and latitude/longitude

Hi need to be able to calculate a bounding box or circle for a Given WGS84 latitude and WGS84 longitude, and distance but have no Idea where to start! The distance from the start lat Lon would be 10KM ...
2
votes
2answers
1k views

ST_Distance versus ST_Distance_Spheroid?

As my client software uses lat/lon coordinates when communicating with my (spherical mercator) postgis database i decided to ST_Transform every geometry to WGS-84. However i noticed that ST_Distance ...
5
votes
2answers
3k views

java vividsolutions jts wgs-84 distance to meters

my (java) project uses com.vividsolutions.jts.geom, which provides a distance function. After some googling I finally found that the return value from this function is in central angle degrees, when ...