Storing high precision latitude/longitude numbers in iOS Core Data

Posted by Bryan on Stack Overflow See other posts from Stack Overflow or by Bryan
Published on 2011-01-03T14:39:12Z Indexed on 2011/01/03 20:54 UTC
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I'm trying to store Latitude/Longitudes in core data. These end up being anywhere from 6-20 digit precision.

And for whatever reason, i had them as floats in Core Data, its rounding them and not giving me the exact values back. I tried "decimal" type, with no luck either.

Are NSStrings my only other option?

EDIT

NSManagedObject:

@interface Event :  NSManagedObject  
{
}

@property (nonatomic, retain) NSDecimalNumber * dec;
@property (nonatomic, retain) NSDate * timeStamp;
@property (nonatomic, retain) NSNumber * flo;
@property (nonatomic, retain) NSNumber * doub;

Here's the code for a sample number that I store into core data:

NSNumber *n = [NSDecimalNumber decimalNumberWithString:@"-97.12345678901234567890123456789"];

Code to access it again:

NSNumber *n = [managedObject valueForKey:@"dec"];
NSNumber *f = [managedObject valueForKey:@"flo"];
NSNumber *d = [managedObject valueForKey:@"doub"];

Printed values:

Printing description of n:
    -97.1234567890124

    Printing description of f:
    <CFNumber 0x603f250 [0xfef3e0]>{value = -97.12345678901235146441, type = kCFNumberFloat64Type}

    Printing description of d:
    <CFNumber 0x6040310 [0xfef3e0]>{value = -97.12345678901235146441, type = kCFNumberFloat64Type}

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