Detailed Description
Computes derivatives of dihedral angle with respect to bond vectors.
Models the dihedral angle formed by three sequentil bond vectors b1, b2, and b3. See Dihedral Interactions in the file dihedral.mod for the definition of the dihedral angle phi and its relationship to these bond vectors
These 3 bond vectors must be passed to the method computeDerivatives() which computes the cosine of the dihedral angle and the derivatives of the cosine with respect to the elements of the bond vectors. This function stores its results in the public members cosPhi, d1, d2, and d3. Upon return:
The scalar member cosPhi is the cosine of the dihdral angle phi.
The elements of the vectors d1, d2, and d3 are derivatives of cosPhi with respect to the elements of the bond vectors b1, b2, and b3.
The function computeAngle(), which is inherited from the Torsion base class, computes only cosPhi, but not the derivatives.
Definition at line 44 of file TorsionForce.h.
#include <TorsionForce.h>
Public Member Functions | |
| bool | computeDerivatives (const Vector &b1, const Vector &b2, const Vector &b3) |
| Compute cosPhi and derivatives. More... | |
 Public Member Functions inherited from Simp::Torsion | |
| bool | computeAngle (const Vector &b1, const Vector &b2, const Vector &b3) |
| Compute cosPhi. More... | |
| double | sinPhi () const |
| Return value of sin(phi) for precomputed cos(phi). More... | |
| double | phi () const |
| Return value of phi in radians for precomputed cos(phi). More... | |
Public Attributes | |
| Vector | d1 |
| Vector of derivatives d1[i] = d(cosPhi)/d(b1[i]) More... | |
| Vector | d2 |
| Vector of derivatives d2[i] = d(cosPhi)/d(b2[i]) More... | |
| Vector | d3 |
| Vector of derivatives d3[i] = d(cosPhi)/d(b3[i]) More... | |
| Public Attributes inherited from Simp::Torsion | |
| double | cosPhi |
| Cosine of dihedral angle. More... | |
Member Function Documentation
|
inline |
Compute cosPhi and derivatives.
- Parameters
-
b1 bond vector from atom 0 to 1. b2 bond vector from atom 1 to 2. b3 bond vector from atom 2 to 3.
- Returns
- 0 if normal, 1 for divide by zero error
Definition at line 83 of file TorsionForce.h.
References Simp::Torsion::cosPhi, Util::Vector::cross(), d1, d2, d3, Util::Vector::dot(), Util::Vector::multiply(), and Util::Vector::square().
Referenced by Simp::CosineDihedral::force(), and Simp::MultiHarmonicDihedral::force().
Member Data Documentation
| Vector Simp::TorsionForce::d1 |
Vector of derivatives d1[i] = d(cosPhi)/d(b1[i])
Definition at line 52 of file TorsionForce.h.
Referenced by computeDerivatives(), Simp::CosineDihedral::force(), and Simp::MultiHarmonicDihedral::force().
| Vector Simp::TorsionForce::d2 |
Vector of derivatives d2[i] = d(cosPhi)/d(b2[i])
Definition at line 57 of file TorsionForce.h.
Referenced by computeDerivatives(), Simp::CosineDihedral::force(), and Simp::MultiHarmonicDihedral::force().
| Vector Simp::TorsionForce::d3 |
Vector of derivatives d3[i] = d(cosPhi)/d(b3[i])
Definition at line 62 of file TorsionForce.h.
Referenced by computeDerivatives(), Simp::CosineDihedral::force(), and Simp::MultiHarmonicDihedral::force().
The documentation for this struct was generated from the following file:
