Struct RegionRestraint 

pub struct RegionRestraint<R: Region>(pub R);

Wraps a Region as a soft-penalty AtomRestraint with quadratic exterior penalty:

penalty(x) = scale2 * max(0, signed_distance(x))²

Gradient uses the analytic chain rule 2 * scale2 * max(0, d) * ∂d/∂x, where ∂d/∂x comes from Region::signed_distance_grad.

Example

use molpack::region::{InsideSphereRegion, RegionExt};
use molpack::{RegionRestraint, AtomRestraint};

let shell = InsideSphereRegion::new([0.0; 3], 10.0)
    .and(InsideSphereRegion::new([0.0; 3], 5.0).not());
let restraint = RegionRestraint(shell);
// At x=(7,0,0) the shell is satisfied → f == 0
assert_eq!(restraint.f(&[7.0, 0.0, 0.0], 1.0, 1.0), 0.0);
// At x=(15,0,0) we are outside the outer sphere → f > 0
assert!(restraint.f(&[15.0, 0.0, 0.0], 1.0, 1.0) > 0.0);

Tuple Fields

0: R

Trait Implementations

impl<R: Region + 'static> AtomRestraint for RegionRestraint<R>

fn f(&self, x: &[F; 3], _scale: F, scale2: F) -> F

fn fg(&self, x: &[F; 3], scale: F, scale2: F, g: &mut [F; 3]) -> F

fn is_parallel_safe(&self) -> bool

fn name(&self) -> &'static str

fn periodic_box(&self) -> Option<([F; 3], [F; 3], [bool; 3])>

Declare that this restraint defines a periodic box for the pair-kernel minimum-image wrap. Return Some((min, max, periodic)) where periodic[k] == true marks axis k as wrapping. Default None means this restraint does not imply PBC.

impl<R: Clone + Region> Clone for RegionRestraint<R>

fn clone(&self) -> RegionRestraint<R>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<R: Copy + Region> Copy for RegionRestraint<R>

impl<R: Debug + Region> Debug for RegionRestraint<R>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.