ForceParam_tag Struct Reference

Used to configure Force_tag class. More...

#include <force.h>

List of all members.

Public Attributes
MD_AtomPrm *	atomprm
MD_BondPrm *	bondprm
MD_AnglePrm *	angleprm
MD_TorsPrm *	dihedprm
MD_TorsPrm *	imprprm
MD_NbfixPrm *	nbfixprm
int32	atomprm_len
int32	bondprm_len
int32	angleprm_len
int32	dihedprm_len
int32	imprprm_len
int32	nbfixprm_len
MD_Atom *	atom
MD_Bond *	bond
MD_Angle *	angle
MD_Tors *	dihed
MD_Tors *	impr
MD_Excl *	excl
int32	atom_len
int32	bond_len
int32	angle_len
int32	dihed_len
int32	impr_len
int32	excl_len
double	xlen
double	ylen
double	zlen
MD_Dvec	center
double	radius1
double	radius2
double	length1
double	length2
double	konst1
double	konst2
int32	exp1
int32	exp2
double	cutoff
double	elec_cutoff
double	vdw_cutoff
double	switchdist
double	elec_const
double	dielectric
double	scaling14
int32	flags

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Detailed Description

Used to configure Force_tag class.

User sets the internal fields of this class in order to configure the evaluation performed by the Force_tag class. The ForceParam_tag class is intended to be setup once and used to initialize the Force_tag class.

The user provides and retains ownership of memory buffer space for all arrays. The force field parameter and topology arrays all follow the MDAPI guidelines as defined by mdtypes.h file. In particular, it is expected that the proper cross-indexing between topology and force field parameter arrays have been established. The best way to do this is to use the MDIO library for reading the relevant force field parameter and topology files.

The parameter atom_len indicates the number of atoms in the system, providing the expected array length of the ForceResult_tag arrays and the pos and wrap arrays passed to force_compute().

The boundary restraint and nonbonded parameters follow the NAMD conventions, as described in its documentation.

The flags indicates what parts of the force field are to be evaluated. It is assigned a bitwise ORed collection of ForceFlags_tag constants.

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Member Data Documentation

MD_Angle* ForceParam_tag::angle

Array of angles.

int32 ForceParam_tag::angle_len

Length of angle array.

MD_AnglePrm* ForceParam_tag::angleprm

Array of angle parameters.

int32 ForceParam_tag::angleprm_len

Length of angle parameters array.

MD_Atom* ForceParam_tag::atom

Array of atoms (contains mass and charge).

int32 ForceParam_tag::atom_len

Length of atom array (number of atoms in system).

MD_AtomPrm* ForceParam_tag::atomprm

Array of atom parameters.

int32 ForceParam_tag::atomprm_len

Length of atom parameters array.

MD_Bond* ForceParam_tag::bond

Array of bonds.

int32 ForceParam_tag::bond_len

Length of bond array.

MD_BondPrm* ForceParam_tag::bondprm

Array of bond parameters.

int32 ForceParam_tag::bondprm_len

Length of bond parameters array.

MD_Dvec ForceParam_tag::center

Center of cell.

double ForceParam_tag::cutoff

Cutoff distance used to define both electrostatics and van der Waals interactions.

double ForceParam_tag::dielectric

Dielectric constant, typically should be set to 1.0.

MD_Tors* ForceParam_tag::dihed

Array of dihedrals.

int32 ForceParam_tag::dihed_len

Length of dihedral array.

MD_TorsPrm* ForceParam_tag::dihedprm

Array of dihedral parameters.

int32 ForceParam_tag::dihedprm_len

Length of dihedral parameters array.

double ForceParam_tag::elec_const

Constant for electrostatic interactions, typically should be defined using MD_COULOMB from MDAPI mdtypes.h file.

double ForceParam_tag::elec_cutoff

Cutoff distance for electrostatics.

MD_Excl* ForceParam_tag::excl

Array of nonbonded exclusions.

int32 ForceParam_tag::excl_len

Length of nonbonded exclusion array.

int32 ForceParam_tag::exp1

Exponent for first harmonic potential. Should be an even positive integer.

int32 ForceParam_tag::exp2

Exponent for second harmonic potential. Should be an even positive integer.

int32 ForceParam_tag::flags

Indicates what parts of force field are to be evaluated. See ForceFlags_tag for details.

MD_Tors* ForceParam_tag::impr

Array of impropers.

int32 ForceParam_tag::impr_len

Length of improper array.

MD_TorsPrm* ForceParam_tag::imprprm

Array of improper parameters.

int32 ForceParam_tag::imprprm_len

Length of improper parameters array.

double ForceParam_tag::konst1

Constant for first harmonic potential.

double ForceParam_tag::konst2

Constant for second harmonic potential.

double ForceParam_tag::length1

For cylindrical restraints: distance at which first potential takes effect along cylinder axis.

double ForceParam_tag::length2

For cylindrical restraints: distance at which second potential takes effect along cylinder axis.

MD_NbfixPrm* ForceParam_tag::nbfixprm

Array of nonbonded parameters to override the combined pairs of atom parameters.

int32 ForceParam_tag::nbfixprm_len

Length of nonbonded parameters array.

double ForceParam_tag::radius1

Distance at which first potential boundary takes effect, measured as radius from center.

double ForceParam_tag::radius2

Distance at which second potential boundary takes effect, measured as radius from center.

double ForceParam_tag::scaling14

Extra multiplicative constant for electrostatic interactions between 1-4 pairs, applied only if FORCE_EXCL_SCAL14 flag is set.

double ForceParam_tag::switchdist

Switching distance for van der Waals (needs to be strictly less than the cutoff).

double ForceParam_tag::vdw_cutoff

Cutoff distance for van der Waals.

double ForceParam_tag::xlen

Size of periodic cell in x direction.

double ForceParam_tag::ylen

Size of periodic cell in y direction.

double ForceParam_tag::zlen

Size of periodic cell in z direction.

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

• force/force.h

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