Table of Contents

Name

kep2kep - interactive transformations between kepler orbit coordinates

Synopsis

kep2kep [parameter=value]

Description

kep2kep is one of the few interactive programs in NEMO, and aids in transforming between different orbit descriptions that exist for Keplerian (2-body) orbits.

Transformations can be done between the following systems

cartesian    x    y    z    vx    vy    vz
spherical    rmod        theta    phi    vrad    vtheta    vphi
scattering    imp.param    imp.angle    init.separ    v_at_inf    theta    phi
tscattering    imp.param    imp.angle    encount.time.    v_at_inf    theta    phi
trueanomaly    a    e    i    OMEGA    omega    f
eccanomaly    a    e    i    OMEGA    omega    E
meananomaly    a    e    i    OMEGA    omega    M
peripassage    a    e    i    OMEGA    omega    T

The final transformation is a combination of only three types of transformation. Within each class of coordinate systems there is one prototype which has the same name as the class. To get from A to B, the first transformation is from A to prototype(A), then from prototype(A) to prototype(B), and finally from prototype(B) to B. these three transformations are called can, trans, cast, respectively.

  
   ___________     trans     __________________________________________
  |           |------------>|                                          |
  | CARTESIAN |<------------|               TRUEANOMALY                |
  |___________|             |__________________________________________|
       |  A                  c |  A             |  A             |  A
       |  |                  a |  | c           |  |             |  |
       |  |                  s |  | a           |  |             |  |   
       |  |                  t |  | n           |  |             |  |
   ____V__|___            _____V__|___     _____V__|____     ____V__|_____
  
  |           |          |            |   |             |   |             |  
  | SPHERICAL |          | ECCANOMALY |   | MEANANOMALY |   | PERIPASSAGE |
  |___________|          |____________|   |_____________|   |_____________|

Parameters

The following parameters are recognized in any order if the keyword is also given:

See Also

kep2kep.c

Files


~/src/nbody/kepler      kep2kep.c

Author

Piet Hut

Update History


Dec 1987    Created - Piet Hut  @ Inst. f. Adv. Study, Princeton, NJ 08540, USA
Mar 1991    adapted for NEMO V2 - no local error() and warning()    PH/PJT
Jun 1991    one more appeasement for GCC    PJT
May 1992    removed local versions of error(*) and warning()    PJT
19-jun-92    fixed all those gcc warnings about local declaration mismatch    PJT


Table of Contents