avoid sqrt computation on cutoffs. make single functions consistent with compute (17b74762) · Commits · 郑智淋 / lammps

src/USER-MISC/pair_coul_shield.cpp

+31 −24

Original line number	Diff line number	Diff line
		@@ -115,8 +115,8 @@ void PairCoulShield::compute(int eflag, int vflag)

		// turn on/off taper function
		if (tap_flag) {
		Tap = calc_Tap(r,sqrt(cutsq[itype][jtype]));
		dTap = calc_dTap(r,sqrt(cutsq[itype][jtype]));
		Tap = calc_Tap(r,cut[itype][jtype]);
		dTap = calc_dTap(r,cut[itype][jtype]);
		} else {Tap = 1.0; dTap = 0.0;}

		forcecoul = qqrd2eqtmpq[j]rdepsdr;
		@@ -348,6 +348,13 @@ double PairCoulShield::single(int i, int j, int itype, int jtype,
		double *q = atom->q;
		double qqrd2e = force->qqrd2e;

		// only computed between different layers as indicated by different molecule ids.

		if (atom->molecule[i] == atom->molecule[j]) {
		fforce = 0.0;
		return 0.0;
		}

		r = sqrt(rsq);
		r3 = rsq*r;
		rarg = 1.0/sigmae[itype][jtype];
		@@ -359,15 +366,15 @@ double PairCoulShield::single(int i, int j, int itype, int jtype,

		// turn on/off taper function
		if (tap_flag) {
		Tap = calc_Tap(r,sqrt(cutsq[itype][jtype]));
		dTap = calc_dTap(r,sqrt(cutsq[itype][jtype]));
		Tap = calc_Tap(r,cut[itype][jtype]);
		dTap = calc_dTap(r,cut[itype][jtype]);
		} else {Tap = 1.0; dTap = 0.0;}

		forcecoul = qqrd2eq[i]q[j]rdepsdr;
		fvc = forcecoulTap - VcdTap/r;
		fforce = factor_coul*fvc;

		if (tap_flag) phishieldec = factor_coulVcTap;
		if (tap_flag) phishieldec = Vc*Tap;
		else phishieldec = Vc - offset[itype][jtype];
		return factor_coul*phishieldec;
		}