When working with CoreLocation, you can use your favorite unit for distance... so long as your favorite unit is the meter. If you want to take distance calculations and display them to the user, you may want to use kilometers instead, or maybe even miles, if you're of the Imperial persuasion.
TTTLocationFormatter gives you a lot of flexibility in the display of coordinates, distances, direction, speed, and velocity. Choose Metric or Imperial, cardinal directions, abbreviations, or degrees, and configure everything else (number of significant digits, etc.), with the associated NSNumberFormatter.
TTTLocationFormatter *locationFormatter = [[[TTTLocationFormatter alloc] init] autorelease];
CLLocation *austin = [[[CLLocation alloc] initWithLatitude:30.2669444 longitude:-97.7427778] autorelease];
CLLocation *pittsburgh = [[[CLLocation alloc] initWithLatitude:40.4405556 longitude:-79.9961111] autorelease];
NSLog(@"%@", [locationFormatter stringFromDistanceAndBearingFromLocation:pittsburgh toLocation:austin]);
// "2,000 km Southwest"
[locationFormatter.numberFormatter setMaximumSignificantDigits:4];
[locationFormatter setBearingStyle:TTTBearingAbbreviationWordStyle];
[locationFormatter setUnitSystem:TTTImperialSystem];
NSLog(@"%@", [locationFormatter stringFromDistanceAndBearingFromLocation:pittsburgh toLocation:austin]);
// "1,218 miles SW"
[locationFormatter setBearingStyle:TTTBearingNumericStyle];
NSLog(@"%@ at %@", [locationFormatter stringFromSpeed:25],[locationFormatter stringFromBearingFromLocation:pittsburgh toLocation:austin]);
// "25 mph at 310°"
[locationFormatter setUsesSignificantDigits:NO];
NSLog(@"%@", [locationFormatter stringFromLocation:austin]);
// (30.2669444, -97.7427778)
TTTLocationFormatter is licensed under the MIT License:
Copyright (c) 2011 Mattt Thompson (http://mattt.me/)
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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