pyoculus.maps.standard_map.standardmap_frev_pure

pyoculus.maps.standard_map.standardmap_frev_pure(y, k)

Inverse of the Tokamap as described in: Balescu, Radu, Mǎdǎlina Vlad, and F. Spineanu. “Tokamap: A Hamiltonian twist map for magnetic field lines in a toroidal geometry.” Physical Review E 58.1 (1998): 951.

The theta funtion is not directly invertible, so a simple Newtons method with analytical derivatives is used to solve for the inverse.

with W(psi) the winding function monotonically increasing from w up.