65 RealType k1, RealType k0) :
67 k4_(k4), k3_(k3), k2_(k2), k1_(k1), k0_(k0) {}
69 void setForceConstant(RealType k4, RealType k3, RealType k2, RealType k1,
78 void getForceConstant(RealType& k4, RealType& k3, RealType& k2,
79 RealType& k1, RealType& k0) {
87 virtual void calcForce(RealType r, RealType& V, RealType& dVdr) {
89 RealType dr2 = dr * dr;
90 RealType dr3 = dr2 * dr;
91 RealType dr4 = dr3 * dr;
93 V = k0_ + k1_ * dr + k2_ * dr2 + k3_ * dr3 + k4_ * dr4;
94 dVdr = k1_ + 2.0 * k2_ * dr + 3.0 * k3_ * dr2 + 4.0 * k4_ * dr3;