lloca.framesnet.frames.Frames

class lloca.framesnet.frames.Frames(matrices=None, is_global=False, det=None, inv=None, is_identity=False, shape=None, device=None, dtype=None)[source]

Bases: object

Bookkeeping class for local frames.

Collection of Lorentz transformations, represented as (…, 4, 4) matrices. Properties like det and inv are cached for performance. Attributes should not be changed after initialization to avoid inconsistencies. The object can be modified with e.g. .reshape(), .expand() and .repeat(), .to().

There are 2 ways to initialize an Frames object, with different arguments: - From matrices: Set matrices and optionally is_global, det, inv - As identity: Set is_identity=True, shape, device, dtype

Parameters:

  • matrices (torch.tensor) – Transformation matrices of shape (…, 4, 4)

  • is_global (bool) – Whether frames are the same for all particles in the point cloud

  • inv (torch.Tensor) – Optional cached inverse of shape (…, 4, 4). If not given, takes a bit of extra time to compute.

  • det (torch.Tensor) – Optional cached determinant of shape (…). If not given, takes a bit of extra time to compute.

  • is_identity (bool) – Sets matrices to diagonal.

  • shape (List[int]) – Specifies matrices.shape[:-2] if is_identity. Otherwise inferred from matrices.

  • device (str) – Specifies device if is_identity. Otherwise inferred from matrices.

  • dtype (torch.dtype) – Specifies dtype if is_identity. Otherwise inferred from matrices.

property device
property dtype
expand(*shape)[source]

Expand the matrices to generate a new object of different shape.

Parameters:

shape (int) – New shape for the matrices. The last two dimensions must be (4, 4).

Return type:

Frames

property metric
repeat(*shape)[source]

Repeat the matrices to generate a new object of different shape.

Parameters:

shape (int) – New shape for the matrices. The last two dimensions must be (4, 4).

Return type:

Frames

reshape(*shape)[source]

Reshape the matrices to generate a new object of different shape.

Parameters:

shape (int) – New shape for the matrices. The last two dimensions must be (4, 4).

Return type:

Frames

property shape
to(dtype=None, device=None)[source]

Move the matrices to a new device and/or dtype.