occ::mults::CartesianMolecule Struct Reference

Collection of precomputed Cartesian sites for a molecule. More...

#include <cartesian_molecule.h>

Public Member Functions
void	update_positions (const Mat3 &rotation, const Vec3 &center, const std::vector< Vec3 > &body_offsets)
	Update lab-frame positions from body-frame offsets + rotation.
void	update_orientation (const Mat3 &new_rotation, const Vec3 &new_center)
	Update both positions AND multipoles for a new orientation.

Static Public Member Functions
static CartesianMolecule	from_lab_sites (const std::vector< std::pair< occ::dma::Mult, Vec3 > > &site_data)
	Build from lab-frame site data (multipole + position pairs).
static CartesianMolecule	from_body_frame (const std::vector< std::pair< occ::dma::Mult, Vec3 > > &body_sites, const Mat3 &rotation, const Vec3 &center)
	Build from body-frame data with rotation and center-of-mass offset.
static CartesianMolecule	from_body_frame_with_rotation (const std::vector< std::pair< occ::dma::Mult, Vec3 > > &body_sites, const Mat3 &rotation, const Vec3 &center)
	Build from body-frame data, retaining body-frame multipoles for rotation support.

Public Attributes
std::vector< CartesianSite >	sites
std::optional< BodyFrameData >	body_data
	Body-frame data for rotation support (optional).

Detailed Description

Collection of precomputed Cartesian sites for a molecule.

Caches the spherical-to-Cartesian conversion and effective_rank so they are computed once per molecule rather than once per pair.

Member Function Documentation

from_body_frame()

static CartesianMolecule occ::mults::CartesianMolecule::from_body_frame ( const std::vector< std::pair< occ::dma::Mult, Vec3 > > &  body_sites, const Mat3 &  rotation, const Vec3 &  center  )

static

Build from body-frame data with rotation and center-of-mass offset.

Does NOT retain body-frame data (positions only).

Parameters

body_sites	Multipoles and body-frame positions
rotation	3x3 rotation matrix (body → lab)
center	Lab-frame center of mass

from_body_frame_with_rotation()

static CartesianMolecule occ::mults::CartesianMolecule::from_body_frame_with_rotation ( const std::vector< std::pair< occ::dma::Mult, Vec3 > > &  body_sites, const Mat3 &  rotation, const Vec3 &  center  )

static

Build from body-frame data, retaining body-frame multipoles for rotation support.

Both positions AND multipoles are rotated to lab.

Parameters

body_sites	Multipoles (body frame) and body-frame positions
rotation	3x3 rotation matrix (body → lab)
center	Lab-frame center of mass

from_lab_sites()

static CartesianMolecule occ::mults::CartesianMolecule::from_lab_sites ( const std::vector< std::pair< occ::dma::Mult, Vec3 > > &  site_data )

static

Build from lab-frame site data (multipole + position pairs).

update_orientation()

void occ::mults::CartesianMolecule::update_orientation	(	const Mat3 &	new_rotation,
		const Vec3 &	new_center
	)

Update both positions AND multipoles for a new orientation.

Requires body_data to be set (via from_body_frame_with_rotation).

update_positions()

void occ::mults::CartesianMolecule::update_positions	(	const Mat3 &	rotation,
		const Vec3 &	center,
		const std::vector< Vec3 > &	body_offsets
	)

Update lab-frame positions from body-frame offsets + rotation.

This avoids re-converting spherical → Cartesian multipoles; only positions change. The effective_rank is rotation-invariant and remains cached.

Member Data Documentation

body_data

std::optional<BodyFrameData> occ::mults::CartesianMolecule::body_data

Body-frame data for rotation support (optional).

sites

std::vector<CartesianSite> occ::mults::CartesianMolecule::sites

---

The documentation for this struct was generated from the following file:

• /home/runner/work/occ/occ/include/occ/mults/cartesian_molecule.h