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orbname - Orbit classification and plotting


orbname in=orbit [parameter=value ...]


orbname attempts to classify an orbit. Currently only orbits in non-rotating triaxial potentials are handled properly. It can distinguish between Box, (long axis) X-Tube, Y-Tube, and (short axis) Z-Tube orbits, based on the predominant angular momentum axis (J_i, i=X,Y,Z). This program cannot distinguish between the so-called inner- and outer-X-Tube orbits. Anything else is labeled as Unknown.

Note that orbits with very long or short periods cannot be reliably classified, either because they have simply not been tracked long enough, or because they may be scattered from one orbital family to another.

orbname will, for each dimension (X,Y,Z), tabulate the number of angular momentum flips and velocity flips, tau (the ratio of mean to dispersion of the angular momentum), nu (the ratio of half the sum of min and max to dispersion), the minimum and maximum angular momentum, and their mean and dispersion.

The ratios tau and nu (under control of the user, see taumin= and numin= below) are used to classify an orbit has having a significant amount of angular moment along an axis. In addition, if an axis has no flips in angular momentum, it is also counted has having angular moment along that axis. This gives a total of three methods to classify orbits. There are output under the names F_Category (J-flipping), T_Category (tau) and N_Category (nu) .


The following parameters are recognized in any order if the keyword is also given:
Input orbit(s), in standard orbit(5NEMO) format.
Minimum mean/sigma J_i needed to count as significant angular momentum. [Default: 1].
Minimum ratio of half the sum of min and max to their sigma J_i needed to count as significant angular momentum. [Default: 1].
Logical to denote if a 6 panels with evolution of angular momentum and (XY,YZ,XZ) need to be plotted. See yapp(5NEMO) . [Default: f]
Maximum time to plot. Default: autoscale from the orbit.
Maximum X,Y,Z extent to plot. Default: autoscale from -rmax to rmax.
Maximum Jx,Jy,Jz extent to plot. Default: autoscale from -jmax to jmax.


Has some problems with planar orbits and bi-axial potentials (such as oblate, prolate and spherical).

See Also

orbdim(1NEMO) , mkorbit(1NEMO) , orbint(1NEMO) , orbit(5MEMO)


Peter Teuben

Update History

3-dec-93    V1.0 Created    PJT
6-dec-93    V1.1 added nu    pjt

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