src/gromacs/gmxlib/nonbonded/nb_kernel_c/nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_c.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
  12  * of the License, or (at your option) any later version.
  13  *
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  35 /*
  36  * Note: this file was generated by the GROMACS c kernel generator.
  37  */
  38 #include "gmxpre.h"
  39
  40 #include "config.h"
  41
  42 #include <math.h>
  43
  44 #include "../nb_kernel.h"
  45 #include "gromacs/legacyheaders/types/simple.h"
  46 #include "gromacs/math/vec.h"
  47 #include "gromacs/legacyheaders/nrnb.h"
  48
  49 /*
  50  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_VF_c
  51  * Electrostatics interaction: ReactionField
  52  * VdW interaction:            Buckingham
  53  * Geometry:                   Water3-Particle
  54  * Calculate force/pot:        PotentialAndForce
  55  */
  56 void
  57 nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_VF_c
  58                     (t_nblist                    * gmx_restrict       nlist,
  59                      rvec                        * gmx_restrict          xx,
  60                      rvec                        * gmx_restrict          ff,
  61                      t_forcerec                  * gmx_restrict          fr,
  62                      t_mdatoms                   * gmx_restrict     mdatoms,
  63                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
  64                      t_nrnb                      * gmx_restrict        nrnb)
  65 {
  66     int              i_shift_offset,i_coord_offset,j_coord_offset;
  67     int              j_index_start,j_index_end;
  68     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
  69     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
  70     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
  71     real             *shiftvec,*fshift,*x,*f;
  72     int              vdwioffset0;
  73     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
  74     int              vdwioffset1;
  75     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
  76     int              vdwioffset2;
  77     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
  78     int              vdwjidx0;
  79     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
  80     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
  81     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
  82     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
  83     real             velec,felec,velecsum,facel,crf,krf,krf2;
  84     real             *charge;
  85     int              nvdwtype;
  86     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
  87     int              *vdwtype;
  88     real             *vdwparam;
  89     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
  90
  91     x                = xx[0];
  92     f                = ff[0];
  93
  94     nri              = nlist->nri;
  95     iinr             = nlist->iinr;
  96     jindex           = nlist->jindex;
  97     jjnr             = nlist->jjnr;
  98     shiftidx         = nlist->shift;
  99     gid              = nlist->gid;
 100     shiftvec         = fr->shift_vec[0];
 101     fshift           = fr->fshift[0];
 102     facel            = fr->epsfac;
 103     charge           = mdatoms->chargeA;
 104     krf              = fr->ic->k_rf;
 105     krf2             = krf*2.0;
 106     crf              = fr->ic->c_rf;
 107     nvdwtype         = fr->ntype;
 108     vdwparam         = fr->nbfp;
 109     vdwtype          = mdatoms->typeA;
 110
 111     /* Setup water-specific parameters */
 112     inr              = nlist->iinr[0];
 113     iq0              = facel*charge[inr+0];
 114     iq1              = facel*charge[inr+1];
 115     iq2              = facel*charge[inr+2];
 116     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 117
 118     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 119     rcutoff          = fr->rcoulomb;
 120     rcutoff2         = rcutoff*rcutoff;
 121
 122     rswitch          = fr->rvdw_switch;
 123     /* Setup switch parameters */
 124     d                = rcutoff-rswitch;
 125     swV3             = -10.0/(d*d*d);
 126     swV4             =  15.0/(d*d*d*d);
 127     swV5             =  -6.0/(d*d*d*d*d);
 128     swF2             = -30.0/(d*d*d);
 129     swF3             =  60.0/(d*d*d*d);
 130     swF4             = -30.0/(d*d*d*d*d);
 131
 132     outeriter        = 0;
 133     inneriter        = 0;
 134
 135     /* Start outer loop over neighborlists */
 136     for(iidx=0; iidx<nri; iidx++)
 137     {
 138         /* Load shift vector for this list */
 139         i_shift_offset   = DIM*shiftidx[iidx];
 140         shX              = shiftvec[i_shift_offset+XX];
 141         shY              = shiftvec[i_shift_offset+YY];
 142         shZ              = shiftvec[i_shift_offset+ZZ];
 143
 144         /* Load limits for loop over neighbors */
 145         j_index_start    = jindex[iidx];
 146         j_index_end      = jindex[iidx+1];
 147
 148         /* Get outer coordinate index */
 149         inr              = iinr[iidx];
 150         i_coord_offset   = DIM*inr;
 151
 152         /* Load i particle coords and add shift vector */
 153         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 154         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 155         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 156         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 157         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 158         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 159         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 160         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 161         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 162
 163         fix0             = 0.0;
 164         fiy0             = 0.0;
 165         fiz0             = 0.0;
 166         fix1             = 0.0;
 167         fiy1             = 0.0;
 168         fiz1             = 0.0;
 169         fix2             = 0.0;
 170         fiy2             = 0.0;
 171         fiz2             = 0.0;
 172
 173         /* Reset potential sums */
 174         velecsum         = 0.0;
 175         vvdwsum          = 0.0;
 176
 177         /* Start inner kernel loop */
 178         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 179         {
 180             /* Get j neighbor index, and coordinate index */
 181             jnr              = jjnr[jidx];
 182             j_coord_offset   = DIM*jnr;
 183
 184             /* load j atom coordinates */
 185             jx0              = x[j_coord_offset+DIM*0+XX];
 186             jy0              = x[j_coord_offset+DIM*0+YY];
 187             jz0              = x[j_coord_offset+DIM*0+ZZ];
 188
 189             /* Calculate displacement vector */
 190             dx00             = ix0 - jx0;
 191             dy00             = iy0 - jy0;
 192             dz00             = iz0 - jz0;
 193             dx10             = ix1 - jx0;
 194             dy10             = iy1 - jy0;
 195             dz10             = iz1 - jz0;
 196             dx20             = ix2 - jx0;
 197             dy20             = iy2 - jy0;
 198             dz20             = iz2 - jz0;
 199
 200             /* Calculate squared distance and things based on it */
 201             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 202             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 203             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 204
 205             rinv00           = gmx_invsqrt(rsq00);
 206             rinv10           = gmx_invsqrt(rsq10);
 207             rinv20           = gmx_invsqrt(rsq20);
 208
 209             rinvsq00         = rinv00*rinv00;
 210             rinvsq10         = rinv10*rinv10;
 211             rinvsq20         = rinv20*rinv20;
 212
 213             /* Load parameters for j particles */
 214             jq0              = charge[jnr+0];
 215             vdwjidx0         = 3*vdwtype[jnr+0];
 216
 217             /**************************
 218              * CALCULATE INTERACTIONS *
 219              **************************/
 220
 221             if (rsq00<rcutoff2)
 222             {
 223
 224             r00              = rsq00*rinv00;
 225
 226             qq00             = iq0*jq0;
 227             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 228             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 229             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 230
 231             /* REACTION-FIELD ELECTROSTATICS */
 232             velec            = qq00*(rinv00+krf*rsq00-crf);
 233             felec            = qq00*(rinv00*rinvsq00-krf2);
 234
 235             /* BUCKINGHAM DISPERSION/REPULSION */
 236             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 237             vvdw6            = c6_00*rinvsix;
 238             br               = cexp2_00*r00;
 239             vvdwexp          = cexp1_00*exp(-br);
 240             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
 241             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 242
 243             d                = r00-rswitch;
 244             d                = (d>0.0) ? d : 0.0;
 245             d2               = d*d;
 246             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 247
 248             dsw              = d2*(swF2+d*(swF3+d*swF4));
 249
 250             /* Evaluate switch function */
 251             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 252             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 253             vvdw            *= sw;
 254
 255             /* Update potential sums from outer loop */
 256             velecsum        += velec;
 257             vvdwsum         += vvdw;
 258
 259             fscal            = felec+fvdw;
 260
 261             /* Calculate temporary vectorial force */
 262             tx               = fscal*dx00;
 263             ty               = fscal*dy00;
 264             tz               = fscal*dz00;
 265
 266             /* Update vectorial force */
 267             fix0            += tx;
 268             fiy0            += ty;
 269             fiz0            += tz;
 270             f[j_coord_offset+DIM*0+XX] -= tx;
 271             f[j_coord_offset+DIM*0+YY] -= ty;
 272             f[j_coord_offset+DIM*0+ZZ] -= tz;
 273
 274             }
 275
 276             /**************************
 277              * CALCULATE INTERACTIONS *
 278              **************************/
 279
 280             if (rsq10<rcutoff2)
 281             {
 282
 283             qq10             = iq1*jq0;
 284
 285             /* REACTION-FIELD ELECTROSTATICS */
 286             velec            = qq10*(rinv10+krf*rsq10-crf);
 287             felec            = qq10*(rinv10*rinvsq10-krf2);
 288
 289             /* Update potential sums from outer loop */
 290             velecsum        += velec;
 291
 292             fscal            = felec;
 293
 294             /* Calculate temporary vectorial force */
 295             tx               = fscal*dx10;
 296             ty               = fscal*dy10;
 297             tz               = fscal*dz10;
 298
 299             /* Update vectorial force */
 300             fix1            += tx;
 301             fiy1            += ty;
 302             fiz1            += tz;
 303             f[j_coord_offset+DIM*0+XX] -= tx;
 304             f[j_coord_offset+DIM*0+YY] -= ty;
 305             f[j_coord_offset+DIM*0+ZZ] -= tz;
 306
 307             }
 308
 309             /**************************
 310              * CALCULATE INTERACTIONS *
 311              **************************/
 312
 313             if (rsq20<rcutoff2)
 314             {
 315
 316             qq20             = iq2*jq0;
 317
 318             /* REACTION-FIELD ELECTROSTATICS */
 319             velec            = qq20*(rinv20+krf*rsq20-crf);
 320             felec            = qq20*(rinv20*rinvsq20-krf2);
 321
 322             /* Update potential sums from outer loop */
 323             velecsum        += velec;
 324
 325             fscal            = felec;
 326
 327             /* Calculate temporary vectorial force */
 328             tx               = fscal*dx20;
 329             ty               = fscal*dy20;
 330             tz               = fscal*dz20;
 331
 332             /* Update vectorial force */
 333             fix2            += tx;
 334             fiy2            += ty;
 335             fiz2            += tz;
 336             f[j_coord_offset+DIM*0+XX] -= tx;
 337             f[j_coord_offset+DIM*0+YY] -= ty;
 338             f[j_coord_offset+DIM*0+ZZ] -= tz;
 339
 340             }
 341
 342             /* Inner loop uses 153 flops */
 343         }
 344         /* End of innermost loop */
 345
 346         tx = ty = tz = 0;
 347         f[i_coord_offset+DIM*0+XX] += fix0;
 348         f[i_coord_offset+DIM*0+YY] += fiy0;
 349         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 350         tx                         += fix0;
 351         ty                         += fiy0;
 352         tz                         += fiz0;
 353         f[i_coord_offset+DIM*1+XX] += fix1;
 354         f[i_coord_offset+DIM*1+YY] += fiy1;
 355         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 356         tx                         += fix1;
 357         ty                         += fiy1;
 358         tz                         += fiz1;
 359         f[i_coord_offset+DIM*2+XX] += fix2;
 360         f[i_coord_offset+DIM*2+YY] += fiy2;
 361         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 362         tx                         += fix2;
 363         ty                         += fiy2;
 364         tz                         += fiz2;
 365         fshift[i_shift_offset+XX]  += tx;
 366         fshift[i_shift_offset+YY]  += ty;
 367         fshift[i_shift_offset+ZZ]  += tz;
 368
 369         ggid                        = gid[iidx];
 370         /* Update potential energies */
 371         kernel_data->energygrp_elec[ggid] += velecsum;
 372         kernel_data->energygrp_vdw[ggid] += vvdwsum;
 373
 374         /* Increment number of inner iterations */
 375         inneriter                  += j_index_end - j_index_start;
 376
 377         /* Outer loop uses 32 flops */
 378     }
 379
 380     /* Increment number of outer iterations */
 381     outeriter        += nri;
 382
 383     /* Update outer/inner flops */
 384
 385     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_VF,outeriter*32 + inneriter*153);
 386 }
 387 /*
 388  * Gromacs nonbonded kernel:   nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_F_c
 389  * Electrostatics interaction: ReactionField
 390  * VdW interaction:            Buckingham
 391  * Geometry:                   Water3-Particle
 392  * Calculate force/pot:        Force
 393  */
 394 void
 395 nb_kernel_ElecRFCut_VdwBhamSw_GeomW3P1_F_c
 396                     (t_nblist                    * gmx_restrict       nlist,
 397                      rvec                        * gmx_restrict          xx,
 398                      rvec                        * gmx_restrict          ff,
 399                      t_forcerec                  * gmx_restrict          fr,
 400                      t_mdatoms                   * gmx_restrict     mdatoms,
 401                      nb_kernel_data_t gmx_unused * gmx_restrict kernel_data,
 402                      t_nrnb                      * gmx_restrict        nrnb)
 403 {
 404     int              i_shift_offset,i_coord_offset,j_coord_offset;
 405     int              j_index_start,j_index_end;
 406     int              nri,inr,ggid,iidx,jidx,jnr,outeriter,inneriter;
 407     real             shX,shY,shZ,tx,ty,tz,fscal,rcutoff,rcutoff2;
 408     int              *iinr,*jindex,*jjnr,*shiftidx,*gid;
 409     real             *shiftvec,*fshift,*x,*f;
 410     int              vdwioffset0;
 411     real             ix0,iy0,iz0,fix0,fiy0,fiz0,iq0,isai0;
 412     int              vdwioffset1;
 413     real             ix1,iy1,iz1,fix1,fiy1,fiz1,iq1,isai1;
 414     int              vdwioffset2;
 415     real             ix2,iy2,iz2,fix2,fiy2,fiz2,iq2,isai2;
 416     int              vdwjidx0;
 417     real             jx0,jy0,jz0,fjx0,fjy0,fjz0,jq0,isaj0;
 418     real             dx00,dy00,dz00,rsq00,rinv00,rinvsq00,r00,qq00,c6_00,c12_00,cexp1_00,cexp2_00;
 419     real             dx10,dy10,dz10,rsq10,rinv10,rinvsq10,r10,qq10,c6_10,c12_10,cexp1_10,cexp2_10;
 420     real             dx20,dy20,dz20,rsq20,rinv20,rinvsq20,r20,qq20,c6_20,c12_20,cexp1_20,cexp2_20;
 421     real             velec,felec,velecsum,facel,crf,krf,krf2;
 422     real             *charge;
 423     int              nvdwtype;
 424     real             rinvsix,rvdw,vvdw,vvdw6,vvdw12,fvdw,fvdw6,fvdw12,vvdwsum,br,vvdwexp,sh_vdw_invrcut6;
 425     int              *vdwtype;
 426     real             *vdwparam;
 427     real             rswitch,swV3,swV4,swV5,swF2,swF3,swF4,d,d2,sw,dsw;
 428
 429     x                = xx[0];
 430     f                = ff[0];
 431
 432     nri              = nlist->nri;
 433     iinr             = nlist->iinr;
 434     jindex           = nlist->jindex;
 435     jjnr             = nlist->jjnr;
 436     shiftidx         = nlist->shift;
 437     gid              = nlist->gid;
 438     shiftvec         = fr->shift_vec[0];
 439     fshift           = fr->fshift[0];
 440     facel            = fr->epsfac;
 441     charge           = mdatoms->chargeA;
 442     krf              = fr->ic->k_rf;
 443     krf2             = krf*2.0;
 444     crf              = fr->ic->c_rf;
 445     nvdwtype         = fr->ntype;
 446     vdwparam         = fr->nbfp;
 447     vdwtype          = mdatoms->typeA;
 448
 449     /* Setup water-specific parameters */
 450     inr              = nlist->iinr[0];
 451     iq0              = facel*charge[inr+0];
 452     iq1              = facel*charge[inr+1];
 453     iq2              = facel*charge[inr+2];
 454     vdwioffset0      = 3*nvdwtype*vdwtype[inr+0];
 455
 456     /* When we use explicit cutoffs the value must be identical for elec and VdW, so use elec as an arbitrary choice */
 457     rcutoff          = fr->rcoulomb;
 458     rcutoff2         = rcutoff*rcutoff;
 459
 460     rswitch          = fr->rvdw_switch;
 461     /* Setup switch parameters */
 462     d                = rcutoff-rswitch;
 463     swV3             = -10.0/(d*d*d);
 464     swV4             =  15.0/(d*d*d*d);
 465     swV5             =  -6.0/(d*d*d*d*d);
 466     swF2             = -30.0/(d*d*d);
 467     swF3             =  60.0/(d*d*d*d);
 468     swF4             = -30.0/(d*d*d*d*d);
 469
 470     outeriter        = 0;
 471     inneriter        = 0;
 472
 473     /* Start outer loop over neighborlists */
 474     for(iidx=0; iidx<nri; iidx++)
 475     {
 476         /* Load shift vector for this list */
 477         i_shift_offset   = DIM*shiftidx[iidx];
 478         shX              = shiftvec[i_shift_offset+XX];
 479         shY              = shiftvec[i_shift_offset+YY];
 480         shZ              = shiftvec[i_shift_offset+ZZ];
 481
 482         /* Load limits for loop over neighbors */
 483         j_index_start    = jindex[iidx];
 484         j_index_end      = jindex[iidx+1];
 485
 486         /* Get outer coordinate index */
 487         inr              = iinr[iidx];
 488         i_coord_offset   = DIM*inr;
 489
 490         /* Load i particle coords and add shift vector */
 491         ix0              = shX + x[i_coord_offset+DIM*0+XX];
 492         iy0              = shY + x[i_coord_offset+DIM*0+YY];
 493         iz0              = shZ + x[i_coord_offset+DIM*0+ZZ];
 494         ix1              = shX + x[i_coord_offset+DIM*1+XX];
 495         iy1              = shY + x[i_coord_offset+DIM*1+YY];
 496         iz1              = shZ + x[i_coord_offset+DIM*1+ZZ];
 497         ix2              = shX + x[i_coord_offset+DIM*2+XX];
 498         iy2              = shY + x[i_coord_offset+DIM*2+YY];
 499         iz2              = shZ + x[i_coord_offset+DIM*2+ZZ];
 500
 501         fix0             = 0.0;
 502         fiy0             = 0.0;
 503         fiz0             = 0.0;
 504         fix1             = 0.0;
 505         fiy1             = 0.0;
 506         fiz1             = 0.0;
 507         fix2             = 0.0;
 508         fiy2             = 0.0;
 509         fiz2             = 0.0;
 510
 511         /* Start inner kernel loop */
 512         for(jidx=j_index_start; jidx<j_index_end; jidx++)
 513         {
 514             /* Get j neighbor index, and coordinate index */
 515             jnr              = jjnr[jidx];
 516             j_coord_offset   = DIM*jnr;
 517
 518             /* load j atom coordinates */
 519             jx0              = x[j_coord_offset+DIM*0+XX];
 520             jy0              = x[j_coord_offset+DIM*0+YY];
 521             jz0              = x[j_coord_offset+DIM*0+ZZ];
 522
 523             /* Calculate displacement vector */
 524             dx00             = ix0 - jx0;
 525             dy00             = iy0 - jy0;
 526             dz00             = iz0 - jz0;
 527             dx10             = ix1 - jx0;
 528             dy10             = iy1 - jy0;
 529             dz10             = iz1 - jz0;
 530             dx20             = ix2 - jx0;
 531             dy20             = iy2 - jy0;
 532             dz20             = iz2 - jz0;
 533
 534             /* Calculate squared distance and things based on it */
 535             rsq00            = dx00*dx00+dy00*dy00+dz00*dz00;
 536             rsq10            = dx10*dx10+dy10*dy10+dz10*dz10;
 537             rsq20            = dx20*dx20+dy20*dy20+dz20*dz20;
 538
 539             rinv00           = gmx_invsqrt(rsq00);
 540             rinv10           = gmx_invsqrt(rsq10);
 541             rinv20           = gmx_invsqrt(rsq20);
 542
 543             rinvsq00         = rinv00*rinv00;
 544             rinvsq10         = rinv10*rinv10;
 545             rinvsq20         = rinv20*rinv20;
 546
 547             /* Load parameters for j particles */
 548             jq0              = charge[jnr+0];
 549             vdwjidx0         = 3*vdwtype[jnr+0];
 550
 551             /**************************
 552              * CALCULATE INTERACTIONS *
 553              **************************/
 554
 555             if (rsq00<rcutoff2)
 556             {
 557
 558             r00              = rsq00*rinv00;
 559
 560             qq00             = iq0*jq0;
 561             c6_00            = vdwparam[vdwioffset0+vdwjidx0];
 562             cexp1_00         = vdwparam[vdwioffset0+vdwjidx0+1];
 563             cexp2_00         = vdwparam[vdwioffset0+vdwjidx0+2];
 564
 565             /* REACTION-FIELD ELECTROSTATICS */
 566             felec            = qq00*(rinv00*rinvsq00-krf2);
 567
 568             /* BUCKINGHAM DISPERSION/REPULSION */
 569             rinvsix          = rinvsq00*rinvsq00*rinvsq00;
 570             vvdw6            = c6_00*rinvsix;
 571             br               = cexp2_00*r00;
 572             vvdwexp          = cexp1_00*exp(-br);
 573             vvdw             = vvdwexp - vvdw6*(1.0/6.0);
 574             fvdw             = (br*vvdwexp-vvdw6)*rinvsq00;
 575
 576             d                = r00-rswitch;
 577             d                = (d>0.0) ? d : 0.0;
 578             d2               = d*d;
 579             sw               = 1.0+d2*d*(swV3+d*(swV4+d*swV5));
 580
 581             dsw              = d2*(swF2+d*(swF3+d*swF4));
 582
 583             /* Evaluate switch function */
 584             /* fscal'=f'/r=-(v*sw)'/r=-(v'*sw+v*dsw)/r=-v'*sw/r-v*dsw/r=fscal*sw-v*dsw/r */
 585             fvdw             = fvdw*sw - rinv00*vvdw*dsw;
 586
 587             fscal            = felec+fvdw;
 588
 589             /* Calculate temporary vectorial force */
 590             tx               = fscal*dx00;
 591             ty               = fscal*dy00;
 592             tz               = fscal*dz00;
 593
 594             /* Update vectorial force */
 595             fix0            += tx;
 596             fiy0            += ty;
 597             fiz0            += tz;
 598             f[j_coord_offset+DIM*0+XX] -= tx;
 599             f[j_coord_offset+DIM*0+YY] -= ty;
 600             f[j_coord_offset+DIM*0+ZZ] -= tz;
 601
 602             }
 603
 604             /**************************
 605              * CALCULATE INTERACTIONS *
 606              **************************/
 607
 608             if (rsq10<rcutoff2)
 609             {
 610
 611             qq10             = iq1*jq0;
 612
 613             /* REACTION-FIELD ELECTROSTATICS */
 614             felec            = qq10*(rinv10*rinvsq10-krf2);
 615
 616             fscal            = felec;
 617
 618             /* Calculate temporary vectorial force */
 619             tx               = fscal*dx10;
 620             ty               = fscal*dy10;
 621             tz               = fscal*dz10;
 622
 623             /* Update vectorial force */
 624             fix1            += tx;
 625             fiy1            += ty;
 626             fiz1            += tz;
 627             f[j_coord_offset+DIM*0+XX] -= tx;
 628             f[j_coord_offset+DIM*0+YY] -= ty;
 629             f[j_coord_offset+DIM*0+ZZ] -= tz;
 630
 631             }
 632
 633             /**************************
 634              * CALCULATE INTERACTIONS *
 635              **************************/
 636
 637             if (rsq20<rcutoff2)
 638             {
 639
 640             qq20             = iq2*jq0;
 641
 642             /* REACTION-FIELD ELECTROSTATICS */
 643             felec            = qq20*(rinv20*rinvsq20-krf2);
 644
 645             fscal            = felec;
 646
 647             /* Calculate temporary vectorial force */
 648             tx               = fscal*dx20;
 649             ty               = fscal*dy20;
 650             tz               = fscal*dz20;
 651
 652             /* Update vectorial force */
 653             fix2            += tx;
 654             fiy2            += ty;
 655             fiz2            += tz;
 656             f[j_coord_offset+DIM*0+XX] -= tx;
 657             f[j_coord_offset+DIM*0+YY] -= ty;
 658             f[j_coord_offset+DIM*0+ZZ] -= tz;
 659
 660             }
 661
 662             /* Inner loop uses 136 flops */
 663         }
 664         /* End of innermost loop */
 665
 666         tx = ty = tz = 0;
 667         f[i_coord_offset+DIM*0+XX] += fix0;
 668         f[i_coord_offset+DIM*0+YY] += fiy0;
 669         f[i_coord_offset+DIM*0+ZZ] += fiz0;
 670         tx                         += fix0;
 671         ty                         += fiy0;
 672         tz                         += fiz0;
 673         f[i_coord_offset+DIM*1+XX] += fix1;
 674         f[i_coord_offset+DIM*1+YY] += fiy1;
 675         f[i_coord_offset+DIM*1+ZZ] += fiz1;
 676         tx                         += fix1;
 677         ty                         += fiy1;
 678         tz                         += fiz1;
 679         f[i_coord_offset+DIM*2+XX] += fix2;
 680         f[i_coord_offset+DIM*2+YY] += fiy2;
 681         f[i_coord_offset+DIM*2+ZZ] += fiz2;
 682         tx                         += fix2;
 683         ty                         += fiy2;
 684         tz                         += fiz2;
 685         fshift[i_shift_offset+XX]  += tx;
 686         fshift[i_shift_offset+YY]  += ty;
 687         fshift[i_shift_offset+ZZ]  += tz;
 688
 689         /* Increment number of inner iterations */
 690         inneriter                  += j_index_end - j_index_start;
 691
 692         /* Outer loop uses 30 flops */
 693     }
 694
 695     /* Increment number of outer iterations */
 696     outeriter        += nri;
 697
 698     /* Update outer/inner flops */
 699
 700     inc_nrnb(nrnb,eNR_NBKERNEL_ELEC_VDW_W3_F,outeriter*30 + inneriter*136);
 701 }