latitude-longitude

问题 How do I get an accurate distance (in meters) given two geo-points (two latitude/longitude pair) ? Possible Duplicates: Distance Between Two GEO Locations Calculating the distance of geo locations Android calculate distance between two locations How to find distance from the latitude and longitude of two locations? 回答1: There's no distance measurement on the iPhone that will give you a resolution of 2 meters. You can use Core Location's -[CLLocation distanceFromLocation: otherLocation] method

问题 How would i create the points of a Geo-Fence(bounding box) using lat and lon and a distance. I have the lat and lon of the center point I have the geofence distance. What would the logic be to create the geo-fence around these multiple points? thanks for any help. 回答1: 1 Convert center lat / lon to cartesian (x,y) in units meter. Then you do all geometry as you have learned in school: 2 Create one corner point of the square, using polar coordinates formula phi = 45 * TO_RADIANS; corner.x =

问题 I have a set of points (stored as lat/lon) for a polygon, I want to compute the lat/lon center point of the polygon in PHP. Basically to do the same thing as the getCenter() function in Google Maps LatLngBounds. Any ideas on how I can achieve this? 回答1: What you are looking for is the centroid of the polygon - which is pretty easy to compute. If you are using latitude/longitude the matter is complicated by the fact the the polygon is actually on the surface of a sphere (ellipsoid). As an

问题 I have a set of points (stored as lat/lon) for a polygon, I want to compute the lat/lon center point of the polygon in PHP. Basically to do the same thing as the getCenter() function in Google Maps LatLngBounds. Any ideas on how I can achieve this? 回答1: What you are looking for is the centroid of the polygon - which is pretty easy to compute. If you are using latitude/longitude the matter is complicated by the fact the the polygon is actually on the surface of a sphere (ellipsoid). As an

问题 I am having problem in passing longitude and latitude format of Pakistan in Twitter Streaming API. This API provides some sample examples of passing longitude and latitude of some cities. The location for San Fransisco in the API location example is given below and it works very well in my program. -122.75,36.8,-121.75,37.8 But I am trying to use the following location to get tweets from Pakistan but the server rejects this location. 71.69,32.01,70.69,33.01 Kindly help me which 4 values

问题 This is related to my earlier question I want to add a "shim" to my map so that the extreme pushpins aren't half-in bounds, half out-of-bounds. I'm on the right track (no pun intended), but my logic is faulty. I wrote this method: // Adapted from Brundritt and Boonaert: https://stackoverflow.com/questions/26937358/can-i-adjust-my-bing-maps-view-locationrect-bounding-box-by-a-small-amount public static Location GetAShimLocation(IList<Location> locations, bool IsForNorthwestCorner) { const

问题 I've got a database of around 400 cities. User selects a city in which he lives, and enters the distance which he is willing to travel (for example, 40kilometers). The city_id is stored into search table, with some other irrelevant information. When user submits the form, he's redirected to results page, on which all results from search table are shown, that meet the criteria, but I want to order them by the distance between city form user's city and the result city, and order the results by

问题 I am trying to convert a lat long string (53.3603, -6.315050000000042) into a google maps object in this format: B: -6.26747649999993 k: 53.339251 I have used this function which works for the long but returns Nan for the lat. function getLatLngFromString(ll) { var lat = ll.replace(/\s*\,.*/, ''); // first 123 var lng = ll.replace(/.*,\s*/, ''); // second ,456 var locate = new google.maps.LatLng(parseFloat(lat), parseFloat(lng)); return locate; } ; I am storing the lat long in a html tag as

问题 I am trying to convert a lat long string (53.3603, -6.315050000000042) into a google maps object in this format: B: -6.26747649999993 k: 53.339251 I have used this function which works for the long but returns Nan for the lat. function getLatLngFromString(ll) { var lat = ll.replace(/\s*\,.*/, ''); // first 123 var lng = ll.replace(/.*,\s*/, ''); // second ,456 var locate = new google.maps.LatLng(parseFloat(lat), parseFloat(lng)); return locate; } ; I am storing the lat long in a html tag as

问题 I am dynamically plotting several points onto a google map. I'm trying to find the best way to find the center of the given points. I've tried using the following: var mapArray = new Array; mapArray[0] = new Array(42, 35.391228, -119.008401); mapArray[1] = new Array(34, 33.874277, -118.131555); mapArray[2] = new Array(214, 32.6922592, -115.4962203); mapArray[3] = new Array(216, 33.3818875, -117.2449785); mapArray[4] = new Array(40, 36.805231, -119.770192); mapArray[5] = new Array(47, 37