## Sunday, March 20, 2016

### PrgCalcPro: Great Circle: Distance Between 2 Places on Earth in kilometers

PrgCalcPro: Great Circle: Distance Between 2 Places on Earth in kilometers

Important: Switch the calculator to Degrees mode before calculation!

Formula:

E = acos( sin N1 sin N2 + cos N1 cos N2 cos (E1 - E2) )
Distance = 6371 * E * π / 180

Store the following values in decimal degrees:
A = N1 (longitude 1), B = E1 (latitude 1)
C = N2 (longitude 2), D = E2 (latitude 2)
Use [ K ] [ swap ] ( ° ' > to convert from H.M to Decimal degrees if needed)

Program:
0: 6A  ;  RA
1: 1C  ;  sin
2: 6C  ;  RC
3: 1C  ;  sin
4: 12  ;  *
5: 6A  ;  RA
6: 1D  ;  cos
7: 6C  ;  RC
8: 1D  ;  cos
9: 12  ;  *
10: 6B  ;  RB
11: 6D  ;  RD
12: 11  ;  -
13: 1D  ;  cos
14: 12  ;  *
15: 10  ;  +
16: 1A  ;  acos
17: 06  ;  6
18: 03  ;  3
19: 07  ;  7
20: 01  ;  1
21: 12  ;  *
22: 20  ;  Pi
23: 12  ;  *
24: 01  ;  1
25: 08  ;  8
26: 00  ;  0
27: 13  ;  /
28: 50  ;  STOP

Example:
Los Angeles (N = 34.05°, E =-118.25°)
Moscow (N = 55.783333°, E = 37.616666°)
Approximate distance: 9,766.5757 km

This blog is property of Edward Shore, 2016.