$LastChangedDate: 27-Juil-2011 $

# CL_oe_cirEqua2car

Circular equatorial adapted to cartesian orbital elements

## Calling Sequence

       [pos_car,vel_car[,jacob]]=CL_oe_cirEqua2car(cir_equa[,mu])

## Description

- Converts orbital elements adapted to near-circular near-equatorial orbits to position and velocity for an elliptic orbit.

  The transformation jacobian is also optionally computed.

  See Orbital elements for more details

## Parameters

cir_equa:

  orbital elements adapted to near-circular near-equatorial orbits [sma;ex;ey;ix;iy;pom+raan+anm] [m,rad] (6xN)

mu :

  (optional) gravitational constant [m^3/s^2] (default value is %CL_mu)

pos_car:

  position [X;Y;Z] [m] (3xN)

vel_car:

  velocity [Vx;Vy;Vz] [m/s] (3xN)

jacob:

  (optional) transformation jacobian d(X,Y,Z,Vx,Vy,Vz)/d(sma,ex,ey,ix,iy,pom+raan+anm) (6x6xN)

## Bibliography

- 1) CNES - MSLIB FORTRAN 90, Volume V (mv_cir_equa_car)

## Authors

- CNES - DCT/SB

## See also

- CL_oe_car2cirEqua

- CL_oe_cir2car

- CL_oe_car2cir

## Examples

    // Example 1
    cir_equa=[42166.712;-7.9d-6;1.1d-4;1.2d-4;-1.16d-4;5.3];
    [pos_car,vel_car,jacob1] = CL_oe_cirEqua2car(cir_equa);
    [cirequa2,jacob2] = CL_oe_car2cirEqua(pos_car,vel_car);