Here’s a reusable function you can use. It includes doctests and data validation: def bilinear_interpolation(x, y, points): ”’Interpolate (x,y) from values associated with four points. The four points are a list of four triplets: (x, y, value). The four points can be in any order. They should form a rectangle. >>> bilinear_interpolation(12, 5.5, … [(10, … Read more
This is some kind of a hack-ish solution, but after the fitBounds, you could zoom one level out, so you get enough padding for your markers. Assume map variable is your reference to the map object; map.setZoom(map.getZoom() – 1);
The Law of Cosines and the Haversine Formula will give identical results assuming a machine with infinite precision. The Haversine formula is more robust to floating point errors. However, today’s machines have double precision of the order of 15 significant figures, and the law of cosines may work just fine for you. Both these formulas … Read more
Here is a javascript function: function measure(lat1, lon1, lat2, lon2){ // generally used geo measurement function var R = 6378.137; // Radius of earth in KM var dLat = lat2 * Math.PI / 180 – lat1 * Math.PI / 180; var dLon = lon2 * Math.PI / 180 – lon1 * Math.PI / 180; var … Read more
Another option: Download the cities database from http://download.geonames.org/export/dump/ Add each city as a lat/long -> City mapping to a spatial index such as an R-Tree (some DBs also have the functionality) Use nearest-neighbour search to find the closest city for any given point Advantages: Does not depend on an external server to be available Very … Read more
You can declare trk by the following ways : – either trk : [{ lat : String, lng : String }] or trk : { type : Array , “default” : [] } In the second case during insertion make the object and push it into the array like db.update({‘Searching criteria goes here’}, { $push … Read more
Thanks! Here is a C# version of OP’s solutions using degrees. It utilises the System.Device.Location.GeoCoordinate class public static GeoCoordinate GetCentralGeoCoordinate( IList<GeoCoordinate> geoCoordinates) { if (geoCoordinates.Count == 1) { return geoCoordinates.Single(); } double x = 0; double y = 0; double z = 0; foreach (var geoCoordinate in geoCoordinates) { var latitude = geoCoordinate.Latitude * Math.PI … Read more
Update: 04/2018: Vincenty distance is deprecated since GeoPy version 1.13 – you should use geopy.distance.distance() instead! The answers above are based on the Haversine formula, which assumes the earth is a sphere, which results in errors of up to about 0.5% (according to help(geopy.distance)). Vincenty distance uses more accurate ellipsoidal models such as WGS-84, and … Read more