Integral Drivers

• Libcint
• PyTorch

Integrals: Base Classes

Base class for integral classes and their actual implementations.

class dxtb._src.integral.base.BaseIntegral(device=None, dtype=None, uplo='l', cutoff=50.0)

Bases: IntegralABC, TensorLike

Base class for integral implementations.

All integral calculations are executed by its child classes.

Parameters:

• device (torch.device | None)

• dtype (torch.dtype | None)

• uplo (Literal['n', 'u', 'l'])

• cutoff (Tensor | float | int | None)

checks(driver)

Check if the driver is setup.

Return type:

None

Parameters:

driver (IntDriver) – Integral driver for the calculation.

Parameters:

driver (IntDriver)

clear()

Clear the integral matrix and gradient.

Return type:

None

normalize(norm=None, **_)

Normalize the integral (changes self.matrix).

Return type:

None

Parameters:

norm (Tensor | None, optional) – Overlap norm to normalize the integral.

Parameters:

• norm (Tensor | None)

• _ (Any)

normalize_gradient(norm=None)

Normalize the gradient (changes self.gradient).

Return type:

None

Parameters:

norm (Tensor) – Overlap norm to normalize the integral.

Parameters:

norm (Tensor | None)

to(device=None, dtype=None)

Returns a copy of the integral on the specified device “device”. This is essentially a wrapper around the to() method of the TensorLike class, but explicitly also moves the integral matrix.

Return type:

Self

Parameters:

device (torch.device | None) – Device to which all associated tensors should be moved.

Returns:

A copy of the integral placed on the specified device.

Return type:

Self

Parameters:

• device (device | None)

• dtype (dtype | None)

to_pt(path=None)

Save the integral matrix to a file.

Return type:

None

Parameters:

path (PathLike | None) – Path to the file where the integral matrix should be saved. If None, the matrix is saved to the default location.

Parameters:

path (str | Path | None)

cutoff: Tensor | float | int | None

Real-space cutoff for integral calculation in Bohr. Defaults to constants.defaults.INTCUTOFF.

family: str | None

Family of the integral implementation (PyTorch or libcint).

property matrix: Tensor

Matrix of the integral.

property requires_grad: bool

Check if any field of the integral class is requires gradient.

Returns:

Flag for gradient requirement.

Return type:

bool

uplo: Literal['n', 'u', 'l']

Whether the matrix of unique shell pairs should be create as a triangular matrix (l: lower, u: upper) or full matrix (n). Defaults to l (lower triangular matrix).