Convert Coordinates to City Name

Convert coordinates to City name?

SWIFT 4.2 : EDIT

MapKit framework does provide a way to get address details from coordinates.

You need to use reverse geocoding of map kit. CLGeocoder class is used to get the location from address and address from the location (coordinates). The method reverseGeocodeLocation will returns the address details from coordinates.

This method accepts CLLocation as a parameter and returns CLPlacemark, which contains address dictionary.

So now above method will be updated as:

@objc func didLongPressMap(sender: UILongPressGestureRecognizer) {

    if sender.state == UIGestureRecognizer.State.began {
        let touchPoint = sender.location(in: mapView)
        let touchCoordinate = mapView.convert(touchPoint, toCoordinateFrom: self.mapView)
        let annotation = MKPointAnnotation()
        annotation.coordinate = touchCoordinate
        annotation.title = "Your position"
        mapView.addAnnotation(annotation) //drops the pin
        print("lat:  \(touchCoordinate.latitude)")
        let num = touchCoordinate.latitude as NSNumber
        let formatter = NumberFormatter()
        formatter.maximumFractionDigits = 4
        formatter.minimumFractionDigits = 4
        _ = formatter.string(from: num)
        print("long: \(touchCoordinate.longitude)")
        let num1 = touchCoordinate.longitude as NSNumber
        let formatter1 = NumberFormatter()
        formatter1.maximumFractionDigits = 4
        formatter1.minimumFractionDigits = 4
        _ = formatter1.string(from: num1)
        self.adressLoLa.text = "\(num),\(num1)"

        // Add below code to get address for touch coordinates.
        let geoCoder = CLGeocoder()
        let location = CLLocation(latitude: touchCoordinate.latitude, longitude: touchCoordinate.longitude)
        geoCoder.reverseGeocodeLocation(location, completionHandler:
            {
                placemarks, error -> Void in

                // Place details
                guard let placeMark = placemarks?.first else { return }

                // Location name
                if let locationName = placeMark.location {
                    print(locationName)
                }
                // Street address
                if let street = placeMark.thoroughfare {
                    print(street)
                }
                // City
                if let city = placeMark.subAdministrativeArea {
                    print(city)
                }
                // Zip code
                if let zip = placeMark.isoCountryCode {
                    print(zip)
                }
                // Country
                if let country = placeMark.country {
                    print(country)
                }
        })
    }
}

How can I get city name from a latitude and longitude point?

This is called Reverse Geocoding

Documentation from Google:
http://code.google.com/apis/maps/documentation/geocoding/#ReverseGeocoding.
Sample Call to Google's geocode Web Service:
http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=true&key=YOUR_KEY

Convert GPS coordinates to a city name / address in Swift

You need to write the code like this:

geocoder.reverseGeocodeLocation(currentLocation, completionHandler: {
            placemarks, error in

                if error == nil && placemarks.count > 0 {
                    self.placeMark = placemarks.last as? CLPlacemark
                    self.adressLabel.text = "\(self.placeMark!.thoroughfare)\n\(self.placeMark!.postalCode) \(self.placeMark!.locality)\n\(self.placeMark!.country)"
                    self.manager.stopUpdatingLocation()
                }
            })

Converting latitude/longitude into city name? (reverse geolocating)

The Google Geocoder, which supports reverse geocoding returns address_components. You just need to pull out the component of the address tagged with locality and political if you just want the city name. If you want states as well they are tagged with administrative_area_level_1

Given the lat/long coordinates, how can we find out the city/country?

The free Google Geocoding API provides this service via a HTTP REST API. Note, the API is usage and rate limited, but you can pay for unlimited access.

Try this link to see an example of the output (this is in json, output is also available in XML)

https://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=true

Convert latitude and longitude to city names, using R

This is possible using the extract function from raster. Or also possible with the over function from the sp package. The approach I have taken below is done using the extract function:

I first used your data provided above to make a data frame, and then got the Brazil shapefile, and used it to extract the city name from the coordinates provided. Here is my code with comments:

library(raster)
library(sp)

#### Coordinates that will be used to search ###
state = c('AL','AL','AL','AL','AL','AL')
river = c('Rio Mundaú', 'Rio Mundaú', 'Rio Mundaú'  , 'Zona dos Can', 'Zona dos Can', 'Zona dos Canais')
lat = c(-9.60, -9.60, -9.60, -9.71, -9.71, -9.71)
long = c(-35.8, -35.8, -35.8, -35.8, -35.8, -35.8)
year = c(2007, 2010, 2011, 2007, 2010, 2011)
contagem = c(5, 5, 9, 5, 7, 9)
mean = c(3, 2, 3.78, 2.2, 2, 2.11)

brazil_data = data.frame(state, river, lat, long, year, contagem, mean)

### Getting the brazil shapefile
brazil = getData('GADM', country = 'Brazil', level = 3, type = "sp")

### Extracting the attributes from the shapefile for the given points
city_names = extract(brazil, brazil_data[, c("long", "lat")])[,12]

### Adding the city names to the Brazil data frame, with the coordinates
brazil_data$City = city_names

This is what we get at the end:

> brazil_data
  state           river   lat  long year contagem mean                 City
1    AL      Rio Mundaú -9.60 -35.8 2007        5 3.00 Santa Luzia do Norte
2    AL      Rio Mundaú -9.60 -35.8 2010        5 2.00 Santa Luzia do Norte
3    AL      Rio Mundaú -9.60 -35.8 2011        9 3.78 Santa Luzia do Norte
4    AL    Zona dos Can -9.71 -35.8 2007        5 2.20     Marechal deodoro
5    AL    Zona dos Can -9.71 -35.8 2010        7 2.00     Marechal deodoro
6    AL Zona dos Canais -9.71 -35.8 2011        9 2.11     Marechal deodoro

Hope this helps!

Converting a city name to coordinates in Swift

You can do it as follow:

import CoreLocation

func getCoordinateFrom(address: String, completion: @escaping(_ coordinate: CLLocationCoordinate2D?, _ error: Error?) -> () ) {
    CLGeocoder().geocodeAddressString(address) { completion($0?.first?.location?.coordinate, $1) }
}

Usage:

let address = "Rio de Janeiro, Brazil"

getCoordinateFrom(address: address) { coordinate, error in
    guard let coordinate = coordinate, error == nil else { return }
    // don't forget to update the UI from the main thread
    DispatchQueue.main.async {
        print(address, "Location:", coordinate) // Rio de Janeiro, Brazil Location: CLLocationCoordinate2D(latitude: -22.9108638, longitude: -43.2045436)
    }

}

Convert coordinates to a place name

The Google Maps API Docs have what seems to be a complete reverse geocoding example. (Note that this is the new V3 API!)

How to get city name from latitude and longitude coordinates in Google Maps?

From a Geocoder object, you can call the getFromLocation(double, double, int) method. It will return a list of Address objects that have a method getLocality().

Geocoder gcd = new Geocoder(context, Locale.getDefault());
List<Address> addresses = gcd.getFromLocation(lat, lng, 1);
if (addresses.size() > 0) {
    System.out.println(addresses.get(0).getLocality());
}
else {
   // do your stuff
}

Convert Coordinates to City Name