# actionAngleVerticalInverse¶

class galpy.actionAngle.actionAngleVerticalInverse(pot=None, Es=[0.1, 0.3], nta=128, setup_interp=False, use_pointtransform=False, pt_deg=7, pt_nxa=301, maxiter=100, angle_tol=1e-12, bisect=False)[source]

Inverse action-angle formalism for one dimensional systems

__init__(pot=None, Es=[0.1, 0.3], nta=128, setup_interp=False, use_pointtransform=False, pt_deg=7, pt_nxa=301, maxiter=100, angle_tol=1e-12, bisect=False)[source]

Initialize an actionAngleVerticalInverse object

Parameters:
• pot (Potential object or list of such objects) – a linearPotential/verticalPotential or list thereof

• Es (numpy.ndarray) – energies of the orbits to map the tori for, will be forcibly sorted (needs to be a dense grid when setting up the object for interpolation with setup_interp=True)

• nta (int) – number of auxiliary angles to sample the torus at when mapping the torus

• setup_interp (bool) – if True, setup interpolation grids that allow any torus within the E range to be accessed through interpolation

• use_pointtransform (bool) – if True, use a point transformation to improve the accuracy of the mapping

• pt_deg (int) – degree of the point transformation polynomial

• pt_nxa (int) – number of points to use in the point transformation

• maxiter (int) – maximum number of iterations of root-finding algorithms

• angle_tol (float) – tolerance for angle root-finding (f(x) is within tol of desired value)

• bisect (bool) – if True, use simple bisection for root-finding, otherwise first try Newton-Raphson (mainly useful for testing the bisection fallback)

Notes

• 2018-04-11 - Started - Bovy (UofT)