# Reference on kuibit.hor_utils¶

The hor_utils module provides functions to perform common operations using horizon(s).

The functions provided are:

kuibit.hor_utils.compute_angular_velocity_vector(horizon1, horizon2, resample=True)[source]

Compute the angular velocity vector.

The information from the apparent horizons is used (contained in the BHDiagnostics files).

The angular velocity vector is computed as

$\Omega = \frac{\mathbf{r} \times \mathbf{r}}{r^2}$
Parameters
Returns

Vectors with the centroid positions

Return type

Tuple of Vector

kuibit.hor_utils.compute_center_of_mass(horizon1, horizon2, resample=True)[source]

Compute the Newtonian center of mass between the centroids of two horizons.

The information from the apparent horizons is used (contained in the BHDiagnostics files). The center of mass is computed with the irreducible mass (which is directly proportional to the area as computed by AHFinderDirect).

Parameters
Returns

Center of mass vector between the two centroids, sampled over where both the horizons are available.

Return type
kuibit.hor_utils.compute_separation(horizon1, horizon2, resample=True)[source]

Compute the coordinate separation between the centroids of two horizons.

The information from the apparent horizons is used (contained in the BHDiagnostics files).

Parameters
Returns

Coordinate distance between the two centroids, sampled over both the horizons are available.

Return type

TimeSeries

kuibit.hor_utils.compute_separation_vector(horizon1, horizon2, resample=True)[source]

Compute the vector coordinate separation between the centroids of two horizons.

The information from the apparent horizons is used (contained in the BHDiagnostics files).

The separation has sign and we compute it as first horizon - second horizon.

Parameters
Returns

Coordinate distance vector between the two centroids, sampled over where both the horizons are available.

Return type