Duplicate check

`pyvoro2.duplicates`

Duplicate / near-duplicate point detection.

Voro++ contains an internal "duplicate" safeguard that can terminate the process (via exit(1)) if it detects two points closer than an absolute threshold (~1e-5 in container distance units).

This module provides a fast Python-side pre-check to detect such cases before calling into the C++ library.

The check is intentionally simple

spatial hashing on an integer grid with cell size == threshold
compare each point only to points in its own grid cell and neighboring 26 cells

Expected complexity is O(n) for typical inputs.

`DuplicateError`

Bases: ValueError

Raised when near-duplicate points are detected.

`duplicate_check(points, *, threshold=1e-05, domain=None, wrap=True, mode='raise', max_pairs=10)`

Detect point pairs closer than an absolute threshold.

Parameters:

Name	Type	Description	Default
`points`	`Any`	Array-like of shape (n, 3).	required
`threshold`	`float`	Absolute distance threshold. The default (1e-5) matches the effective Voro++ duplicate check (distance < 1e-5).	`1e-05`
`domain`	`Domain \| None`	Optional domain. If provided and `wrap=True`, points are first remapped into the primary periodic domain for periodic domains, matching what Voro++ will do internally.	`None`
`wrap`	`bool`	Whether to remap points into the primary domain when `domain` has periodicity.	`True`
`mode`	`Literal['raise', 'warn', 'return']`	Behavior when duplicates are found: - 'raise' (default): raise :class:`DuplicateError` - 'warn': emit a RuntimeWarning and return the pairs - 'return': return the pairs without warnings	`'raise'`
`max_pairs`	`int`	Maximum number of pairs to include in the report.	`10`

Returns:

Type	Description
`tuple[DuplicatePair, ...]`	Tuple of DuplicatePair records (possibly empty).

:::