## NonDimensionalOrbit:

Path: Orbit/OrbitMechanics

```% Dimensionalize or non-dimensionalize an orbit.
dir determines the direction. dir = 0 or dir omitted
will non-dimensionalizes r, v, t and mu. r, v and t may be vectors.

We non-dimesionalize as follows:

Quantity	Units       Nondimensionalizing Constanst
r           [L]         rRef
t           [T]         rRef/sqrt(mu/rRef)
v           [L/T]       sqrt(mu/rRef)
mu          [L^3/T^2]	mu
accel       [L/T^2]     mu/rRef^2

sqrt(mu/r) = v = L/T so we pick T = rRef/sqrt(mu/r)

Non-dimensional units are often better for estimation and optimization.
For circular orbits the nominal orbit radius is best for rRef. For
other orbits, such as a geosynchronous transfer orbit you can pick
the mean orbit. When using nondimensional units you must
non-dimensionalize the external accelerations by multiplying by
fAcc.

Type NonDimensionalOrbit for a simulation of a circular planar orbit
at 1 AU from the sun. It will plot non-dimensional and dimensional
units. In non-dimensional units r and v will oscillate between +/- 1.

Since version 2014.1
--------------------------------------------------------------------------
Form:
[r, v, t, mu, fAcc] =  NonDimensionalOrbit( r, v, t, mu, rRef, dir )
--------------------------------------------------------------------------

------
Inputs
------
r       (3,:)   Position vectors
v       (3,:)   Velocity vectors
t       (1,:)   Time vector
mu      (1,1)   Gravitational constant
rRef	(1,1)   Reference length
dir     (1,1)   0 or no input means non-dimensionalize

-------
Outputs
-------
r       (3,:)   Position vectors
v       (3,:)   Velocity vectors
t       (1,:)   Time vector
mu      (1,1)   Gravitational constant
fAcc    (1,1)   Acceleration scaling

--------------------------------------------------------------------------
```

## Children:

```AC: ACData/ACTConstants
SC: BasicOrbit/Period
SC: BasicOrbit/RHSOrbit
SC: SCData/sCTConstants
Common: CommonData/Constants
Common: CommonData/SwooshWatermark
Common: CommonData/xSplashSmall
Common: Database/Constant
Common: General/CellToMat
Common: General/DeleteCell
Common: General/MatToCell
Common: General/Watermark
Common: Graphics/NewFig
Common: Graphics/Plot2D
Common: Graphics/PltStyle
Common: Graphics/TimeLabl
Math: Integration/RK4
Math: Linear/Mag
```

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