geolocation

Coca-Cola seems to have nailed it pretty well. Even before any user interaction, they manage to know where you are at their Facebook page : This works in IE, so no HTML5 involved (and after all, Facebook won't recognize the navigator object in Javascript). How do they do this? First of all, I don't think it can be done using javascript. Here's how you can do it using a server side language, like PHP. If you take a closer look of the page you provided (coca cola landing tab) you can see that selection of the country works even if the user is not logged in with facebook. When you set up a

I'm rebuilding Lovers on Facebook with Sinatra & Redis, and I want: Set operations for managing requests & relationships between users Geospatial indexing to display nearby app users Current Redis Implementation Each user has two Redis ordered sets ( reqSent & reqRecv ) that store uids. The SCORE that we order the requests by is the time (UNIX timestamp) the request was made. I am using ordered sets instead of lists because a user may only make The request type (rid) is encoded as a number and prepended to the uid. (rid|uid) E.g., for the user with uid=100, we might have: 100:reqSent => ["1

I have a db contain customers longitude and latitude, I have a search form in which the user will enter log/lat and distance dropdown contain 50miles, 100miles,.... and when the user click search I want to write a linq query to get all customers from the db which are in this distance radius. How to make this using C# and linq? Update: I found this https://stackoverflow.com/a/1654365/20126 but this gives a square not radius Fung A little modification of my answer to a similar question : // radius is the distance in meters var center = new GeoCoordinate(latitude, longitude); var result =

I have the following Firebase Database JSON data structure: { "Post List" : { "-KUlvg8mCEGfY5ZSKCou" : { "addedByUser" : "7llQbPdy2NV7aO337h7ap0qLOhC3", "content" : "Post1", "cost" : "$450", "duration" : "Daily", "latitude" : "25.0879721592719", "longitude" : "55.1487715855458", "number" : "01234567890", "timestamp" : "Posted on: Sun 23 Oct" } }, "Post Locations" : { "-KUlvg8mCEGfY5ZSKCou" : { ".priority" : "thrnwznh58", "g" : "thrnwznh58", "l" : [ 25.0879721592719, 55.1487715855458 ] } }, "User Locations" : { "7llQbPdy2NV7aO337h7ap0qLOhC3" : { ".priority" : "thrnwypqu9", "g" : "thrnwypqu9",

Problem: I'm trying to make it so that it uses the user's location all the time and constantly checks to see if it is within 5 miles of the CLLocationCoordinate2D points I have set. If so, it sends a alert if the app is open or a notification if the app is closed. Useful Information: In my project I have 4 swift files: Locations.swift holds the CLLocationCoordinate2D points. Utilities.swift holds a simple alert. UserLocation.swift retrieves and updates the user's location GeoLocationViewController.swift monitors the locations Note: Some code may not be in the right place or relevant, I was

I need to calculate the distance between GPS co-ordinates to calculate distance traveled. I've tried both the Haversine and Vincenty algorithms, which work fine on my desktop PC, but when I port the code to the dsPIC, they return 0 for points that are close (within several meters) due to a lack of floating point precision and poor implementations of sin and cos. For my use case, my points will be no more than 10 meters apart and will all fall within 10km of each other. I've tried the following algorithm and the results seem ok: double dist(double latA, double lonA, double latB, double lonB) {