Function within 

pub fn within(
    positions: &[[f32; 3]],
    query: &AtomSelection,
    target: &AtomSelection,
    cutoff: f32,
    backend: SpatialBackend,
    periodic: Option<&PeriodicBox>,
    context: &ExecutionContext,
) -> Result<AtomSelection, SpatialError>

Selects query atoms within cutoff of any target atom.

Target atoms are included when they also belong to query, matching the conventional meaning of within rather than around.

Errors

Returns the same errors as crate::pairs_within.