├── Haversine.h
└── Haversine.m


/Haversine.h:
--------------------------------------------------------------------------------
 1 | //
 2 | //  haversine.h
 3 | //
 4 | //  Created by Carsten Nielsen on 23/04/09.
 5 | //
 6 | 
 7 | #import <Foundation/Foundation.h>
 8 | 
 9 | extern float const HAVERSINE_RADS_PER_DEGREE;
10 | extern float const HAVERSINE_MI_RADIUS;
11 | extern float const HAVERSINE_KM_RADIUS;
12 | extern float const HAVERSINE_M_PER_KM;
13 | extern float const HAVERSINE_F_PER_MI;
14 | 
15 | @interface Haversine : NSObject {
16 |   float lat1;
17 |   float lon1;
18 |   float lat2;
19 |   float lon2;
20 | }
21 | 
22 | @property float lat1;
23 | @property float lon1;
24 | @property float lat2;
25 | @property float lon2;
26 | 
27 | - (id)init;
28 | - (id)initWithLat1:(float)newLat1
29 |               lon1:(float)newLon1
30 |               lat2:(float)newLat2
31 |               lon2:(float)newLon2;
32 | - (float)distance;
33 | - (float)toKilometers;
34 | - (float)toMeters;
35 | - (float)toMiles;
36 | - (float)toFeet;
37 | 
38 | @end
39 | 


--------------------------------------------------------------------------------
/Haversine.m:
--------------------------------------------------------------------------------
 1 | //
 2 | //  haversine.m
 3 | //
 4 | //  Created by Carsten Nielsen.
 5 | //
 6 | 
 7 | #import "Haversine.h"
 8 | 
 9 | float const HAVERSINE_RADS_PER_DEGREE = 0.0174532925199433;
10 | float const HAVERSINE_MI_RADIUS = 3956.0;
11 | float const HAVERSINE_KM_RADIUS = 6371.0;
12 | float const HAVERSINE_M_PER_KM = 1000.0;
13 | float const HAVERSINE_F_PER_MI = 5282.0;
14 | 
15 | 
16 | @implementation Haversine
17 | 
18 | @synthesize lat1, lon1, lat2, lon2;
19 | 
20 | - (id)init {
21 |   return [self initWithLat1:0.0 lon1:0.0 lat2:0.0 lon2:0.0];
22 | }
23 | 
24 | - (id)initWithLat1:(float)newLat1
25 |               lon1:(float)newLon1
26 |               lat2:(float)newLat2
27 |               lon2:(float)newLon2 {
28 |   self = [super init]; 
29 |   if (self) {
30 |     self.lat1 = newLat1;
31 |     self.lon1 = newLon1;
32 |     self.lat2 = newLat2;
33 |     self.lon2 = newLon2;
34 |   }
35 |   return self; 
36 | }
37 | 
38 | - (float)distance {
39 |   float lat1Rad = lat1 * HAVERSINE_RADS_PER_DEGREE;
40 |   float lat2Rad = lat2 * HAVERSINE_RADS_PER_DEGREE;
41 |   float dLonRad = ((lon2 - lon1) * HAVERSINE_RADS_PER_DEGREE);
42 |   float dLatRad = ((lat2 - lat1) * HAVERSINE_RADS_PER_DEGREE);
43 |   float a = pow(sin(dLatRad / 2), 2) + cos(lat1Rad) * cos(lat2Rad) * pow(sin(dLonRad / 2), 2);
44 |   return (2 * atan2(sqrt(a), sqrt(1 - a)));
45 | }
46 | 
47 | - (float)toKilometers {
48 |   return [self distance] * HAVERSINE_KM_RADIUS;
49 | }
50 | 
51 | - (float)toMeters {
52 |   return [self toKilometers] * HAVERSINE_M_PER_KM;
53 | }
54 | 
55 | - (float)toMiles {
56 |   return [self distance] * HAVERSINE_MI_RADIUS; 
57 | }
58 | 
59 | - (float)toFeet {
60 |   return [self toMiles] * HAVERSINE_F_PER_MI;
61 | }
62 | 
63 | @end
64 | 


--------------------------------------------------------------------------------