# poliastro.core.propagation¶

Low level propagation algorithms.

## Package Contents¶

### Functions¶

 func_twobody(t0, u_, k) Differential equation for the initial value two body problem. cowell(k, r, v, tofs, rtol=1e-11, *, events=None, f=func_twobody) danby(k, r0, v0, tof, numiter=20, rtol=1e-08) Kepler solver for both elliptic and parabolic orbits based on Danby's danby_coe(k, p, ecc, inc, raan, argp, nu, tof, numiter=20, rtol=1e-08) farnocchia_coe(k, p, ecc, inc, raan, argp, nu, tof) farnocchia gooding(k, r0, v0, tof, numiter=150, rtol=1e-08) Solves the Elliptic Kepler Equation with a cubic convergence and gooding_coe(k, p, ecc, inc, raan, argp, nu, tof, numiter=150, rtol=1e-08) markley(k, r0, v0, tof) Solves the kepler problem by a non-iterative method. Relative error is markley_coe(k, p, ecc, inc, raan, argp, nu, tof) mikkola(k, r0, v0, tof, rtol=None) Raw algorithm for Mikkola's Kepler solver. mikkola_coe(k, p, ecc, inc, raan, argp, nu, tof) pimienta pimienta_coe(k, p, ecc, inc, raan, argp, nu, tof) recseries recseries_coe(k, p, ecc, inc, raan, argp, nu, tof, method='rtol', order=8, numiter=100, rtol=1e-08) vallado(k, r0, v0, tof, numiter) Solves Kepler's Equation by applying a Newton-Raphson method.