Конвертировать десятичные градусы в градусы Десятичные минуты (DDM)

Question

Я использовал следующие методы для преобразования Decimal Degrees в Degrees Minutes Seconds (DMS), но мне также необходимо его преобразовать в Degrees Decimals Minutes (DDM).

Как я могу преобразовать Decimal DegreesDMS, а также DMS назад в Decimal Degrees?

+ (NSString *)latitudeCoordinate:(CLLocationCoordinate2D)coordinate { 

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

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

    return result; 

} 


+ (NSString *)longitudeCoordinate:(CLLocationCoordinate2D)coordinate { 

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

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

    return result; 

} 

+ (double)degreesStringToDecimal:(NSString*)string { 

    // split the string 
    NSArray *splitDegs = [string componentsSeparatedByString:@"\u00B0"]; // unicode for degree symbol 
    NSArray *splitMins = [splitDegs[1] componentsSeparatedByString:@"'"]; 
    NSArray *splitSecs = [splitMins[1] componentsSeparatedByString:@"\""]; 

    // get each segment of the dms string 
    NSString *degreesString = splitDegs[0]; 
    NSArray *directionArray = [degreesString componentsSeparatedByString:@" "]; 
    NSString *minutesString = splitMins[0]; 
    NSString *secondsString = splitSecs[0]; 
    NSString *direction = directionArray[0]; 
    degreesString = directionArray[1]; 

    // convert degrees 
    double degrees = [degreesString doubleValue]; 

    // convert minutes 
    double minutes = [minutesString doubleValue]/60; // 60 degrees in a minute 

    // convert seconds 
    double seconds = [secondsString doubleValue]/3600; // 60 seconds in a minute, or 3600 in a degree 

    // add them all together 
    double decimal = degrees + minutes + seconds; 

    // determine if this is negative. south and west would be negative values 
    if ([direction.uppercaseString isEqualToString:@"W"] || [direction.uppercaseString isEqualToString:@"S"]) 
    { 
     decimal = -decimal; 
    } 

    return decimal; 
} 

Answer 1

Я понял. Вот два метода, которые я использую для lat и lon.

+ (NSString *)DDMfromDEClatitude:(CLLocationDegrees)coordinate { 

    NSString *coordinateString = [NSString stringWithFormat:@"%f", coordinate]; 
    NSArray *splitCoordinates = [coordinateString componentsSeparatedByString:@"."]; 
    int before = [splitCoordinates[0] intValue]; 
    NSString *after = [NSString stringWithFormat:@"0.%@", splitCoordinates[1]]; 
    double afterDouble = [after doubleValue]; 
    afterDouble = afterDouble * 60; 
    NSString *direction = before >= 0 ? @"N" : @"S"; 

    if (before < 0) { 
     before = -before; 
    } 

    return [NSString stringWithFormat:@"%@ %i° %.3f", direction, before, afterDouble]; 
} 

+ (NSString *)DDMfromDEClongitude:(CLLocationDegrees)coordinate { 

    NSString *coordinateString = [NSString stringWithFormat:@"%f", coordinate]; 
    NSArray *splitCoordinates = [coordinateString componentsSeparatedByString:@"."]; 
    int before = [splitCoordinates[0] intValue]; 
    NSString *after = [NSString stringWithFormat:@"0.%@", splitCoordinates[1]]; 
    double afterDouble = [after doubleValue]; 
    afterDouble = afterDouble * 60; 
    NSString *direction = before >= 0 ? @"E" : @"W"; 

    if (before < 0) { 
     before = -before; 
    } 

    return [NSString stringWithFormat:@"%@ %i° %.3f", direction, before, afterDouble]; 
} 

Вот метод, чтобы преобразовать обратно из DDM в DEC:

+ (double)DECfromDDM:(NSString *)ddmString { 

    NSArray *split = [ddmString componentsSeparatedByString:@"\u00B0 "]; 
    NSArray *splitDegs = [split[0] componentsSeparatedByString:@" "]; 
    double minutes = [split[1] doubleValue]/60; 
    NSString *directionString = splitDegs[0]; 
    int direction = [splitDegs[1] intValue]; 
    double coordinate = direction + minutes; 

    if ([directionString.uppercaseString isEqualToString:@"W"] || [directionString.uppercaseString isEqualToString:@"S"]) { 
     coordinate = -coordinate; 
    } 

    return coordinate; 
} 

Я использовал координатно конвертер, чтобы проверить мои расчеты были правильными: http://www.pgc.umn.edu/tools/conversion