Geographic coordinate conversion from NSString in DMS format into decimal in CLLocationDegrees (aka double).http://en.wikipedia.org/wiki/Geographic_coordinate_conversion43° 36' 15.894" N => 43.60442

DMSToDecimal

//  http://en.wikipedia.org/wiki/Geographic_coordinate_conversion
//  43° 36' 15.894" N => 43.60442

#import "DMSToDecimal.h"

BOOL DMSToDecimal(NSString* dms, CLLocationDegrees *decimal) {
    CLLocationDegrees degres=0, minutes=0, seconds=0;
    NSScanner *scanner = [NSScanner scannerWithString:dms];
    scanner.charactersToBeSkipped = [NSCharacterSet whitespaceAndNewlineCharacterSet];
    if (![scanner scanDouble:&degres]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (![scanner scanString:@"°" intoString:NULL]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (![scanner scanDouble:&minutes]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (![scanner scanString:@"'" intoString:NULL]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (![scanner scanDouble:&seconds]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (![scanner scanString:@"\"" intoString:NULL]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    NSString* hemisphereOUmeridien = nil;
    if (![scanner scanCharactersFromSet:[NSCharacterSet characterSetWithCharactersInString:@"EWNSewns"] intoString:&hemisphereOUmeridien]) {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    hemisphereOUmeridien = [hemisphereOUmeridien uppercaseString];
    CLLocationDegrees sign;
    if ([hemisphereOUmeridien isEqualToString:@"W"] || [hemisphereOUmeridien isEqualToString:@"S"]) {
        sign = -1;
    } else if ([hemisphereOUmeridien isEqualToString:@"E"] || [hemisphereOUmeridien isEqualToString:@"N"]) {
        sign = 1;
    } else {
        NSLog(@"%s wrong coordinate %@", __FUNCTION__, dms);
        return NO;
    }
    if (decimal)
        *decimal = sign * (floor(degres) + floor(minutes)/60.0 + seconds/3600.0);
    return YES;
}