Welcome to GravHopper’s documentation

“They told me computers could only do arithmetic.” – Grace Hopper

GravHopper is a gravitational N-body simulation code written by Jeremy Bailin, named in honor both of pioneering computer scientist Grace Hopper, and the leapfrog integration algorithm.

GravHopper combines a simple Python interface for ease of use with a C backend for speed. The code is designed to be easy to understand and use for teaching in advanced undergraduate and graduate courses, while being efficient and scalable enough to quickly run simulations with reasonable numbers of particles – anything that doesn’t require cluster-scale computing is doable with GravHopper. It includes the ability to add external forces, and interfaces well with the galpy, gala, and pynbody packages.

Contents:

• Installation
  • Dependencies
  • Install with pip (recommended)
  • Install from github
• Basic Usage
  • Create a Simulation object
  • Create initial conditions
  • Add external forces (optional)
  • Run the simulation
  • Analyze the output
• Examples
  • Equilibrium Plummer sphere
  • Satellite disrupting in an external halo potential
  • Reflex motion of the Sun due to Venus and Jupiter
  • Sample a galpy NFW spherical distribution function
  • Bobbing and oscillating orbit in a galactic disk
  • Galaxy merger
  • Initial conditions from cosmological simulation output
• Reference
  • Simulation
  • IC
  • unitconverter
  • jbgrav
  • Exceptions

Indices and tables

• Index

• Search Page