rubix.galaxy package

Subpackages

• rubix.galaxy.input_handler package
  • Submodules
  • rubix.galaxy.input_handler.base module
    • BaseHandler
      • BaseHandler.get_galaxy_data()
      • BaseHandler.get_particle_data()
      • BaseHandler.get_simulation_metadata()
      • BaseHandler.get_units()
      • BaseHandler.to_rubix()
    • create_rubix_galaxy()
  • rubix.galaxy.input_handler.factory module
  • rubix.galaxy.input_handler.illustris module
    • IllustrisHandler
      • IllustrisHandler.get_galaxy_data()
      • IllustrisHandler.get_particle_data()
      • IllustrisHandler.get_simulation_metadata()
      • IllustrisHandler.get_units()
  • Module contents
    • BaseHandler
      • BaseHandler.get_galaxy_data()
      • BaseHandler.get_particle_data()
      • BaseHandler.get_simulation_metadata()
      • BaseHandler.get_units()
      • BaseHandler.to_rubix()
    • IllustrisAPI
      • IllustrisAPI.DEFAULT_FIELDS
      • IllustrisAPI.get_particle_data()
      • IllustrisAPI.get_subhalo()
      • IllustrisAPI.load_galaxy()
    • get_input_handler()

Submodules

rubix.galaxy.alignment module

rubix.galaxy.alignment.apply_init_rotation(positions: Float[Array, '...'], rotation_matrix: Float[Array, '...']) → Float[Array, '...']

Apply a rotation matrix to a set of positions.

Parameters:

• positions (jnp.ndarray) – The positions of the particles.

• rotation_matrix (jnp.ndarray) – The rotation matrix.

Returns:

The rotated positions as a jnp.ndarray.

rubix.galaxy.alignment.apply_rotation(positions: Float[Array, '* 3'], alpha: float, beta: float, gamma: float) → Float[Array, '* 3']

Apply a rotation to a set of positions given Euler angles.

Parameters:

• positions (jnp.ndarray) – The positions of the particles.

• alpha (float) – Rotation around the x-axis in degrees

• beta (float) – Rotation around the y-axis in degrees

• gamma (float) – Rotation around the z-axis in degrees

Returns:

The rotated positions as a jnp.ndarray.

rubix.galaxy.alignment.center_particles(rubixdata: object, key: str) → object

Center the stellar particles around the galaxy center.

Parameters:

• rubixdata (object) – The RubixData object.

• key (str) – The key to the particle data.

• stellar_coordinates (jnp.ndarray) – The coordinates of the particles.

• stellar_velocities (jnp.ndarray) – The velocities of the particles.

• galaxy_center (jnp.ndarray) – The center of the galaxy.

Returns:

The RubixData object with the centered particles, which contain of a new set of coordinates and velocities as jnp.ndarray.

Example

>>> from rubix.galaxy.alignment import center_particles
>>> rubixdata = center_particles(rubixdata, "stars")

rubix.galaxy.alignment.euler_rotation_matrix(alpha: float, beta: float, gamma: float) → Float[Array, '3 3']

Create a 3x3 rotation matrix given Euler angles (in degrees)

Parameters:

• alpha (float) – Rotation around the x-axis in degrees

• beta (float) – Rotation around the y-axis in degrees

• gamma (float) – Rotation around the z-axis in degrees

Returns:

The rotation matrix as a jnp.ndarray.

rubix.galaxy.alignment.moment_of_inertia_tensor(positions: Float[Array, '...'], masses: Float[Array, '...'], halfmass_radius: Float[Array, '...'] | float) → Float[Array, '...']

Calculate the moment of inertia tensor for a given set of positions and masses within the half-light radius. Assumes the galaxy is already centered.

Parameters:

• positions (jnp.ndarray) – The positions of the particles.

• masses (jnp.ndarray) – The masses of the particles.

• half_light_radius (float) – The half-light radius of the galaxy.

Returns:

The moment of inertia tensor as a jnp.ndarray.

Example

>>> from rubix.galaxy.alignment import moment_of_inertia_tensor
>>> I = moment_of_inertia_tensor(rubixdata.stars.coords, rubixdata.stars.mass, rubixdata.galaxy.half_light_radius)

rubix.galaxy.alignment.rotate_galaxy(positions: Float[Array, '* 3'], velocities: Float[Array, '* 3'], masses: Float[Array, '...'], halfmass_radius: Float[Array, '...'], alpha: float, beta: float, gamma: float) → Tuple[Float[Array, '* 3'], Float[Array, '* 3']]

Orientate the galaxy by applying a rotation matrix to the positions of the particles.

Parameters:

• positions (jnp.ndarray) – The positions of the particles.

• velocities (jnp.ndarray) – The velocities of the particles.

• masses (jnp.ndarray) – The masses of the particles.

• halfmass_radius (float) – The half-mass radius of the galaxy.

• alpha (float) – Rotation around the x-axis in degrees

• beta (float) – Rotation around the y-axis in degrees

• gamma (float) – Rotation around the z-axis in degrees

Returns:

The rotated positions and velocities as a jnp.ndarray.

rubix.galaxy.alignment.rotation_matrix_from_inertia_tensor(I: Float[Array, '...']) → Float[Array, '...']

Calculate 3x3 rotation matrix by diagonalization of the moment of inertia tensor.

Parameters:

I (jnp.ndarray) – The moment of inertia tensor.

Returns:

The rotation matrix as a jnp.ndarray.

Module contents