system_from_simulation: Rebuild an orbit_system from a simulation snapshot

In orbitr: A Tidy Physics Engine for Building and Visualizing Orbital Simulations

Rebuild an orbit_system from a simulation snapshot

Description

Takes the state of every body at one time step of a simulation and returns a new 'orbit_system' with those positions and velocities as its initial conditions. This is the bridge from a finished run back to a system you can modify (add a body, remove one, change a velocity) and simulate again.

Usage

system_from_simulation(sim_data, time = NULL, G = NULL)

Arguments

sim_data	A tibble output from [simulate_system()].
time	The simulation time (in seconds) of the snapshot to use. Defaults to the last time step. Snaps to the closest available time.
G	The gravitational constant for the new system. Defaults to the value recorded by [simulate_system()] in the '"G"' attribute of 'sim_data', or to [gravitational_constant] if that is absent.

Value

An ‘orbit_system' whose bodies have the snapshot’s positions and velocities.

Examples

sim <- create_system() |>
  add_sun() |>
  add_planet("Earth", parent = "Sun") |>
  simulate_system(time_step = seconds_per_day, duration = seconds_per_day * 100)

# Where everything was on day 100, as a system ready to simulate again
later <- system_from_simulation(sim)
later

orbitr documentation built on Oct. 2, 2026, 1:06 a.m.