galpy.orbit.Orbit.e¶
-
Orbit.
e
(analytic=False, pot=None, **kwargs)¶ NAME:
ePURPOSE:
calculate the eccentricity, either numerically from the numerical orbit integration or using analytical meansINPUT:
analytic(= False) compute this analytically
pot - potential to use for analytical calculation
For 3D orbits different approximations for analytic=True are available (see the EccZmaxRperiRap method of actionAngle modules):
type= (‘staeckel’) type of actionAngle module to use
- ‘adiabatic’: assuming motion splits into R and z
- ‘staeckel’: assuming motion splits into u and v of prolate spheroidal coordinate system, exact for Staeckel potentials (incl. all spherical potentials)
- ‘spherical’: for spherical potentials, exact
+actionAngle module setup kwargs for the corresponding actionAngle modules (actionAngleAdiabatic, actionAngleStaeckel, and actionAngleSpherical)
OUTPUT:
eccentricity [*input_shape]HISTORY:
2019-02-25 - Written - Bovy (UofT)