Swift 将十进制坐标转换为度、分、秒、方向

Question

我怎样才能将其转换为 swift？我最好的猜测是所有的 int 都变成了 var。删除所有导致“的@”。另外，如果有的话可以为我指出一个很好的来源，以了解事物如何转换。

- (NSString*)coordinateString {

int latSeconds = (int)(self.latitude * 3600);
int latDegrees = latSeconds / 3600;
latSeconds = ABS(latSeconds % 3600);
int latMinutes = latSeconds / 60;
latSeconds %= 60;

int longSeconds = (int)(self.longitude * 3600);
int longDegrees = longSeconds / 3600;
longSeconds = ABS(longSeconds % 3600);
int longMinutes = longSeconds / 60;
longSeconds %= 60;

NSString* result = [NSString stringWithFormat:@"%d°%d'%d\"%@ %d°%d'%d\"%@",
                    ABS(latDegrees),
                    latMinutes,
                    latSeconds,
                    latDegrees >= 0 ? @"N" : @"S",
                    ABS(longDegrees),
                    longMinutes,
                    longSeconds,
                    longDegrees >= 0 ? @"E" : @"W"];

return result;    
}

我尝试转换它，但 Xcode 证明我错了。使用 ABS 重新发布修复建议。现在看起来正确吗？

func coordinateString {

var latSeconds = (Int8)(self.latitude * 3600);
var latDegrees = latSeconds / 3600;
latSeconds = abs(latSeconds % 3600);
var latMinutes = latSeconds / 60;
latSeconds %= 60;

var longSeconds = (Int8)(self.longitude * 3600);
var longDegrees = longSeconds / 3600;
longSeconds = abs(longSeconds % 3600);
var longMinutes = longSeconds / 60;
longSeconds %= 60;

    var result = (String(format: "%d°%d'%d\"%@ %d°%d'%d\"%@"),
abs(latDegrees),
latMinutes,
latSeconds,
latDegrees >= 0 ? "N" : "S",
abs(longDegrees),
longMinutes,
longSeconds,
longDegrees >= 0 ? "E" : "W",

return result;
}

Answer 1

Xcode 12 • Swift 5 或更高版本

extension BinaryFloatingPoint {
    var dms: (degrees: Int, minutes: Int, seconds: Int) {
        var seconds = Int(self * 3600)
        let degrees = seconds / 3600
        seconds = abs(seconds % 3600)
        return (degrees, seconds / 60, seconds % 60)
    }
}

---

extension CLLocation {
    var dms: String { latitude + " " + longitude }
    var latitude: String {
        let (degrees, minutes, seconds) = coordinate.latitude.dms
        return String(format: "%d°%d'%d\"%@", abs(degrees), minutes, seconds, degrees >= 0 ? "N" : "S")
    }
    var longitude: String {
        let (degrees, minutes, seconds) = coordinate.longitude.dms
        return String(format: "%d°%d'%d\"%@", abs(degrees), minutes, seconds, degrees >= 0 ? "E" : "W")
    }
}

---

let latitude = -22.9133950
let longitude = -43.2007100
let location = CLLocation(latitude: latitude, longitude: longitude)
location.latitude  // "22°54'48"S"
location.longitude // "43°12'2"W"
location.dms       // "22°54'48"S 43°12'2"W"

Answer 2

我刚刚编辑了 Leo Dabus 答案以将这些字符串作为单独的值。如果对他人有帮助：

Swift 3 和 Swift 4

func getLocationDegreesFrom(latitude: Double) -> String {

    var latSeconds = Int(latitude * 3600)

    let latDegrees = latSeconds / 3600

    latSeconds = abs(latSeconds % 3600)

    let latMinutes = latSeconds / 60

    latSeconds %= 60

    return String(

        format: "%d°%d'%d\"%@",
        abs(latDegrees),
        latMinutes,
        latSeconds,
        latDegrees >= 0 ? "N" : "S"

    )

}

func getLocationDegreesFrom(longitude: Double) -> String {

    var longSeconds = Int(longitude * 3600)

    let longDegrees = longSeconds / 3600

    longSeconds = abs(longSeconds % 3600)

    let longMinutes = longSeconds / 60

    longSeconds %= 60

    return String(

        format: "%d°%d'%d\"%@",
        abs(longDegrees),
        longMinutes,
        longSeconds,
        longDegrees >= 0 ? "E" : "W"

    )

}

Answer 3

我拿了Leo Dabus的代码，修复了当纬度或经度的值小于零时与检测基本方向相关的错误，我意思是当我们在南半球或本初子午线以西。

我们不能用 Swift 表示负零，所以我们在下面的表达式中失去了负号：

let latDegrees = latSeconds / 3600

这个错误也使得表达式：

latDegrees >= 0 ? "N" : "S"

总是返回 N（北），从不返回 S（南）。

这是我的代码版本（Swift 5 和 Xcode 10）：

func coordinate() -> (latitude: String, longitude: String) {

    // This function converts from DD (decimal degrees) to DMS (degrees, minutes and seconds)

    // Calculating the degrees, minutes and seconds for the given latitude value (DD)

    var latitudeSeconds = latitude * 3600

    let latitudeDegrees = latitudeSeconds / 3600

    latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 3600)

    let latitudeMinutes = latitudeSeconds / 60

    latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 60)

    // Calculating the degrees, minutes and seconds for the given longitude value (DD)

    var longitudeSeconds = longitude * 3600

    let longitudeDegrees = longitudeSeconds / 3600

    longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 3600)

    let longitudeMinutes = longitudeSeconds / 60

    longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 60)

    // Analyzing if it's North or South. (Latitude)

    let latitudeCardinalDirection = latitudeDegrees >= 0 ? "N" : "S"

    // Analyzing if it's East or West. (Longitude)

    let longitudeCardinalDirection = longitudeDegrees >= 0 ? "E" : "W"

    // Final strings with format <degrees>°<minutes>'<seconds>"<cardinal direction>

    let latitudeDescription = String(format:"%.2f°%.2f'%.2f\"%@",
                                     abs(latitudeDegrees), abs(latitudeMinutes),
                                     abs(latitudeSeconds), latitudeCardinalDirection)

    let longitudeDescription = String(format:"%.2f°%.2f'%.2f\"%@",
                                      abs(longitudeDegrees), abs(longitudeMinutes),
                                      abs(longitudeSeconds), longitudeCardinalDirection)

    return (latitudeDescription, longitudeDescription)

} // coordinate

我还选择使用 Double 来处理精度，例如，我更喜欢显示两位小数。

这段代码的屏幕输出会是这样的：

0.17°10.34'20.53"S 78.48°28.59'35.52"W

Answer 4

基于 David Seek 和 Josué V. Herrera 代码

func latlon2DMS(latitude: Double) -> String {
    var latitudeSeconds = latitude * 3600
    let latitudeDegrees = latitudeSeconds / 3600
    latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 3600)
    let latitudeMinutes = latitudeSeconds / 60
    latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 60)
    let latitudeCardinalDirection = latitudeDegrees >= 0 ? "N" : "S"
    let latitudeDescription = String(format: "%.2f° %.2f' %.2f\" %@",
                                     abs(latitudeDegrees), abs(latitudeMinutes),
                                     abs(latitudeSeconds), latitudeCardinalDirection)
    return latitudeDescription
}

func latlon2DMS(longitude: Double) -> String {
    var longitudeSeconds = longitude * 3600
    let longitudeDegrees = longitudeSeconds / 3600
    longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 3600)
    let longitudeMinutes = longitudeSeconds / 60
    longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 60)
    let longitudeCardinalDirection = longitudeDegrees >= 0 ? "E" : "W"
    let longitudeDescription = String(format: "%.2f° %.2f' %.2f\" %@",
                                      abs(longitudeDegrees), abs(longitudeMinutes),
                                      abs(longitudeSeconds), longitudeCardinalDirection)
    return longitudeDescription
}

调用它

print(latlon2DMS(latitude: coordLat))
print(latlon2DMS(longitude: coordLong))

latitude.text = latlon2DMS(latitude: coordLat)
longitude.text = latlon2DMS(longitude: coordLong)

Answer 5

我稍微修改了 Josue V. 的代码，使其在一个经常更新位置的计时器中工作

        if( CLLocationManager.authorizationStatus() == .authorizedWhenInUse ||
            CLLocationManager.authorizationStatus() ==  .authorizedAlways){
        let currentLocation = locationManager.location
        var latitudeSeconds = currentLocation!.coordinate.latitude * 3600
        let latitudeDegrees = latitudeSeconds / 3600

            latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 3600)

        let latitudeMinutes = latitudeSeconds / 60

            latitudeSeconds = latitudeSeconds.truncatingRemainder(dividingBy: 60)

        var longitudeSeconds = currentLocation!.coordinate.longitude * 3600
        let longitudeDegrees = longitudeSeconds / 3600

            longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 3600)

        let longitudeMinutes = longitudeSeconds / 60

            longitudeSeconds = longitudeSeconds.truncatingRemainder(dividingBy: 60)

        let latitudeCardinalDirection = latitudeDegrees >= 0 ? "N" : "S"
        let longitudeCardinalDirection = longitudeDegrees >= 0 ? "E" : "W"

        let latitudeDescription = String(format:"%.2f°%.2f'%.2f\"%@",
                                         abs(latitudeDegrees), abs(latitudeMinutes),
                                         abs(latitudeSeconds), latitudeCardinalDirection)

        let longitudeDescription = String(format:"%.2f°%.2f'%.2f\"%@",
                                          abs(longitudeDegrees), abs(longitudeMinutes),
                                          abs(longitudeSeconds), longitudeCardinalDirection)

        cell5.text = latitudeDescription + " " + longitudeDescription

        }
    }

还有计时器

timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(coordinate), userInfo: nil, repeats: true)