Currently we only take the analytical derivative up to order 4 in solver/__init__.py function get_axial_derivatives. After using the assumption r_0 = 0 to simplify the formulas (see #3) we should be able to calculate the derivatives of higher order analytically.
See also formula 13.16a in Peter W. Hawkes. Principles of Electron Optics, Basic Geometrical Optics. 2017.
Currently we only take the analytical derivative up to order 4 in
solver/__init__.pyfunctionget_axial_derivatives. After using the assumptionr_0 = 0to simplify the formulas (see #3) we should be able to calculate the derivatives of higher order analytically.See also formula
13.16ain Peter W. Hawkes. Principles of Electron Optics, Basic Geometrical Optics. 2017.