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root/OpenMD/trunk/src/parallel/ForceMatrixDecomposition.cpp
Revision: 1567
Committed: Tue May 24 21:24:45 2011 UTC (13 years, 11 months ago) by gezelter
Original Path: branches/development/src/parallel/ForceMatrixDecomposition.cpp
File size: 21025 byte(s)
Log Message:
Fixed some busted stuff in buildNeighborList

File Contents

# User Rev Content
1 gezelter 1539 /*
2     * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved.
3 chuckv 1538 *
4     * The University of Notre Dame grants you ("Licensee") a
5     * non-exclusive, royalty free, license to use, modify and
6     * redistribute this software in source and binary code form, provided
7     * that the following conditions are met:
8     *
9     * 1. Redistributions of source code must retain the above copyright
10     * notice, this list of conditions and the following disclaimer.
11     *
12     * 2. Redistributions in binary form must reproduce the above copyright
13     * notice, this list of conditions and the following disclaimer in the
14     * documentation and/or other materials provided with the
15     * distribution.
16     *
17     * This software is provided "AS IS," without a warranty of any
18     * kind. All express or implied conditions, representations and
19     * warranties, including any implied warranty of merchantability,
20     * fitness for a particular purpose or non-infringement, are hereby
21     * excluded. The University of Notre Dame and its licensors shall not
22     * be liable for any damages suffered by licensee as a result of
23     * using, modifying or distributing the software or its
24     * derivatives. In no event will the University of Notre Dame or its
25     * licensors be liable for any lost revenue, profit or data, or for
26     * direct, indirect, special, consequential, incidental or punitive
27     * damages, however caused and regardless of the theory of liability,
28     * arising out of the use of or inability to use software, even if the
29     * University of Notre Dame has been advised of the possibility of
30     * such damages.
31     *
32     * SUPPORT OPEN SCIENCE! If you use OpenMD or its source code in your
33     * research, please cite the appropriate papers when you publish your
34     * work. Good starting points are:
35     *
36     * [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).
37     * [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).
38     * [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).
39     * [4] Vardeman & Gezelter, in progress (2009).
40     */
41 gezelter 1549 #include "parallel/ForceMatrixDecomposition.hpp"
42 gezelter 1539 #include "math/SquareMatrix3.hpp"
43 gezelter 1544 #include "nonbonded/NonBondedInteraction.hpp"
44     #include "brains/SnapshotManager.hpp"
45 chuckv 1538
46 gezelter 1541 using namespace std;
47 gezelter 1539 namespace OpenMD {
48 chuckv 1538
49 gezelter 1544 /**
50     * distributeInitialData is essentially a copy of the older fortran
51     * SimulationSetup
52     */
53    
54 gezelter 1549 void ForceMatrixDecomposition::distributeInitialData() {
55 gezelter 1551 snap_ = sman_->getCurrentSnapshot();
56     storageLayout_ = sman_->getStorageLayout();
57 gezelter 1567 nLocal_ = snap_->getNumberOfAtoms();
58     nGroups_ = snap_->getNumberOfCutoffGroups();
59 chuckv 1538
60 gezelter 1567 #ifdef IS_MPI
61    
62     AtomCommIntRow = new Communicator<Row,int>(nLocal_);
63     AtomCommRealRow = new Communicator<Row,RealType>(nLocal_);
64     AtomCommVectorRow = new Communicator<Row,Vector3d>(nLocal_);
65     AtomCommMatrixRow = new Communicator<Row,Mat3x3d>(nLocal_);
66 chuckv 1538
67 gezelter 1567 AtomCommIntColumn = new Communicator<Column,int>(nLocal_);
68     AtomCommRealColumn = new Communicator<Column,RealType>(nLocal_);
69     AtomCommVectorColumn = new Communicator<Column,Vector3d>(nLocal_);
70     AtomCommMatrixColumn = new Communicator<Column,Mat3x3d>(nLocal_);
71 gezelter 1541
72 gezelter 1567 cgCommIntRow = new Communicator<Row,int>(nGroups_);
73     cgCommVectorRow = new Communicator<Row,Vector3d>(nGroups_);
74     cgCommIntColumn = new Communicator<Column,int>(nGroups_);
75     cgCommVectorColumn = new Communicator<Column,Vector3d>(nGroups_);
76 gezelter 1551
77 gezelter 1567 nAtomsInRow_ = AtomCommIntRow->getSize();
78     nAtomsInCol_ = AtomCommIntColumn->getSize();
79     nGroupsInRow_ = cgCommIntRow->getSize();
80     nGroupsInCol_ = cgCommIntColumn->getSize();
81    
82 gezelter 1551 // Modify the data storage objects with the correct layouts and sizes:
83 gezelter 1567 atomRowData.resize(nAtomsInRow_);
84 gezelter 1551 atomRowData.setStorageLayout(storageLayout_);
85 gezelter 1567 atomColData.resize(nAtomsInCol_);
86 gezelter 1551 atomColData.setStorageLayout(storageLayout_);
87 gezelter 1567 cgRowData.resize(nGroupsInRow_);
88 gezelter 1551 cgRowData.setStorageLayout(DataStorage::dslPosition);
89 gezelter 1567 cgColData.resize(nGroupsInCol_);
90 gezelter 1551 cgColData.setStorageLayout(DataStorage::dslPosition);
91 gezelter 1549
92 gezelter 1544 vector<vector<RealType> > pot_row(N_INTERACTION_FAMILIES,
93 gezelter 1567 vector<RealType> (nAtomsInRow_, 0.0));
94 gezelter 1544 vector<vector<RealType> > pot_col(N_INTERACTION_FAMILIES,
95 gezelter 1567 vector<RealType> (nAtomsInCol_, 0.0));
96 gezelter 1551
97    
98 gezelter 1544 vector<RealType> pot_local(N_INTERACTION_FAMILIES, 0.0);
99 gezelter 1549
100 gezelter 1544 // gather the information for atomtype IDs (atids):
101 gezelter 1547 vector<int> identsLocal = info_->getIdentArray();
102 gezelter 1567 identsRow.reserve(nAtomsInRow_);
103     identsCol.reserve(nAtomsInCol_);
104 gezelter 1549
105     AtomCommIntRow->gather(identsLocal, identsRow);
106     AtomCommIntColumn->gather(identsLocal, identsCol);
107    
108     AtomLocalToGlobal = info_->getGlobalAtomIndices();
109     AtomCommIntRow->gather(AtomLocalToGlobal, AtomRowToGlobal);
110     AtomCommIntColumn->gather(AtomLocalToGlobal, AtomColToGlobal);
111    
112     cgLocalToGlobal = info_->getGlobalGroupIndices();
113     cgCommIntRow->gather(cgLocalToGlobal, cgRowToGlobal);
114     cgCommIntColumn->gather(cgLocalToGlobal, cgColToGlobal);
115 gezelter 1541
116 gezelter 1544 // still need:
117     // topoDist
118     // exclude
119 chuckv 1538 #endif
120 gezelter 1539 }
121    
122 chuckv 1538
123    
124 gezelter 1549 void ForceMatrixDecomposition::distributeData() {
125 gezelter 1551 snap_ = sman_->getCurrentSnapshot();
126     storageLayout_ = sman_->getStorageLayout();
127 chuckv 1538 #ifdef IS_MPI
128 gezelter 1540
129 gezelter 1539 // gather up the atomic positions
130 gezelter 1551 AtomCommVectorRow->gather(snap_->atomData.position,
131     atomRowData.position);
132     AtomCommVectorColumn->gather(snap_->atomData.position,
133     atomColData.position);
134 gezelter 1539
135     // gather up the cutoff group positions
136 gezelter 1551 cgCommVectorRow->gather(snap_->cgData.position,
137     cgRowData.position);
138     cgCommVectorColumn->gather(snap_->cgData.position,
139     cgColData.position);
140 gezelter 1539
141     // if needed, gather the atomic rotation matrices
142 gezelter 1551 if (storageLayout_ & DataStorage::dslAmat) {
143     AtomCommMatrixRow->gather(snap_->atomData.aMat,
144     atomRowData.aMat);
145     AtomCommMatrixColumn->gather(snap_->atomData.aMat,
146     atomColData.aMat);
147 gezelter 1539 }
148    
149     // if needed, gather the atomic eletrostatic frames
150 gezelter 1551 if (storageLayout_ & DataStorage::dslElectroFrame) {
151     AtomCommMatrixRow->gather(snap_->atomData.electroFrame,
152     atomRowData.electroFrame);
153     AtomCommMatrixColumn->gather(snap_->atomData.electroFrame,
154     atomColData.electroFrame);
155 gezelter 1539 }
156     #endif
157     }
158    
159 gezelter 1549 void ForceMatrixDecomposition::collectIntermediateData() {
160 gezelter 1551 snap_ = sman_->getCurrentSnapshot();
161     storageLayout_ = sman_->getStorageLayout();
162 gezelter 1539 #ifdef IS_MPI
163    
164 gezelter 1551 if (storageLayout_ & DataStorage::dslDensity) {
165    
166     AtomCommRealRow->scatter(atomRowData.density,
167     snap_->atomData.density);
168    
169     int n = snap_->atomData.density.size();
170 gezelter 1541 std::vector<RealType> rho_tmp(n, 0.0);
171 gezelter 1551 AtomCommRealColumn->scatter(atomColData.density, rho_tmp);
172 gezelter 1539 for (int i = 0; i < n; i++)
173 gezelter 1551 snap_->atomData.density[i] += rho_tmp[i];
174 gezelter 1539 }
175 chuckv 1538 #endif
176 gezelter 1539 }
177    
178 gezelter 1549 void ForceMatrixDecomposition::distributeIntermediateData() {
179 gezelter 1551 snap_ = sman_->getCurrentSnapshot();
180     storageLayout_ = sman_->getStorageLayout();
181 chuckv 1538 #ifdef IS_MPI
182 gezelter 1551 if (storageLayout_ & DataStorage::dslFunctional) {
183     AtomCommRealRow->gather(snap_->atomData.functional,
184     atomRowData.functional);
185     AtomCommRealColumn->gather(snap_->atomData.functional,
186     atomColData.functional);
187 gezelter 1539 }
188    
189 gezelter 1551 if (storageLayout_ & DataStorage::dslFunctionalDerivative) {
190     AtomCommRealRow->gather(snap_->atomData.functionalDerivative,
191     atomRowData.functionalDerivative);
192     AtomCommRealColumn->gather(snap_->atomData.functionalDerivative,
193     atomColData.functionalDerivative);
194 gezelter 1539 }
195 chuckv 1538 #endif
196     }
197 gezelter 1539
198    
199 gezelter 1549 void ForceMatrixDecomposition::collectData() {
200 gezelter 1551 snap_ = sman_->getCurrentSnapshot();
201     storageLayout_ = sman_->getStorageLayout();
202     #ifdef IS_MPI
203     int n = snap_->atomData.force.size();
204 gezelter 1544 vector<Vector3d> frc_tmp(n, V3Zero);
205 gezelter 1541
206 gezelter 1551 AtomCommVectorRow->scatter(atomRowData.force, frc_tmp);
207 gezelter 1541 for (int i = 0; i < n; i++) {
208 gezelter 1551 snap_->atomData.force[i] += frc_tmp[i];
209 gezelter 1541 frc_tmp[i] = 0.0;
210     }
211 gezelter 1540
212 gezelter 1551 AtomCommVectorColumn->scatter(atomColData.force, frc_tmp);
213 gezelter 1540 for (int i = 0; i < n; i++)
214 gezelter 1551 snap_->atomData.force[i] += frc_tmp[i];
215 gezelter 1540
216    
217 gezelter 1551 if (storageLayout_ & DataStorage::dslTorque) {
218 gezelter 1541
219 gezelter 1551 int nt = snap_->atomData.force.size();
220 gezelter 1544 vector<Vector3d> trq_tmp(nt, V3Zero);
221 gezelter 1541
222 gezelter 1551 AtomCommVectorRow->scatter(atomRowData.torque, trq_tmp);
223 gezelter 1541 for (int i = 0; i < n; i++) {
224 gezelter 1551 snap_->atomData.torque[i] += trq_tmp[i];
225 gezelter 1541 trq_tmp[i] = 0.0;
226     }
227 gezelter 1540
228 gezelter 1551 AtomCommVectorColumn->scatter(atomColData.torque, trq_tmp);
229 gezelter 1540 for (int i = 0; i < n; i++)
230 gezelter 1551 snap_->atomData.torque[i] += trq_tmp[i];
231 gezelter 1540 }
232    
233 gezelter 1567 nLocal_ = snap_->getNumberOfAtoms();
234 gezelter 1544
235     vector<vector<RealType> > pot_temp(N_INTERACTION_FAMILIES,
236 gezelter 1567 vector<RealType> (nLocal_, 0.0));
237 gezelter 1540
238 gezelter 1544 for (int i = 0; i < N_INTERACTION_FAMILIES; i++) {
239 gezelter 1549 AtomCommRealRow->scatter(pot_row[i], pot_temp[i]);
240 gezelter 1541 for (int ii = 0; ii < pot_temp[i].size(); ii++ ) {
241     pot_local[i] += pot_temp[i][ii];
242     }
243     }
244 gezelter 1539 #endif
245 chuckv 1538 }
246 gezelter 1551
247 chuckv 1538
248 gezelter 1551 Vector3d ForceMatrixDecomposition::getIntergroupVector(int cg1, int cg2){
249     Vector3d d;
250    
251     #ifdef IS_MPI
252     d = cgColData.position[cg2] - cgRowData.position[cg1];
253     #else
254     d = snap_->cgData.position[cg2] - snap_->cgData.position[cg1];
255     #endif
256    
257     snap_->wrapVector(d);
258     return d;
259     }
260    
261    
262     Vector3d ForceMatrixDecomposition::getAtomToGroupVectorRow(int atom1, int cg1){
263    
264     Vector3d d;
265    
266     #ifdef IS_MPI
267     d = cgRowData.position[cg1] - atomRowData.position[atom1];
268     #else
269     d = snap_->cgData.position[cg1] - snap_->atomData.position[atom1];
270     #endif
271    
272     snap_->wrapVector(d);
273     return d;
274     }
275    
276     Vector3d ForceMatrixDecomposition::getAtomToGroupVectorColumn(int atom2, int cg2){
277     Vector3d d;
278    
279     #ifdef IS_MPI
280     d = cgColData.position[cg2] - atomColData.position[atom2];
281     #else
282     d = snap_->cgData.position[cg2] - snap_->atomData.position[atom2];
283     #endif
284    
285     snap_->wrapVector(d);
286     return d;
287     }
288    
289     Vector3d ForceMatrixDecomposition::getInteratomicVector(int atom1, int atom2){
290     Vector3d d;
291    
292     #ifdef IS_MPI
293     d = atomColData.position[atom2] - atomRowData.position[atom1];
294     #else
295     d = snap_->atomData.position[atom2] - snap_->atomData.position[atom1];
296     #endif
297    
298     snap_->wrapVector(d);
299     return d;
300     }
301    
302     void ForceMatrixDecomposition::addForceToAtomRow(int atom1, Vector3d fg){
303     #ifdef IS_MPI
304     atomRowData.force[atom1] += fg;
305     #else
306     snap_->atomData.force[atom1] += fg;
307     #endif
308     }
309    
310     void ForceMatrixDecomposition::addForceToAtomColumn(int atom2, Vector3d fg){
311     #ifdef IS_MPI
312     atomColData.force[atom2] += fg;
313     #else
314     snap_->atomData.force[atom2] += fg;
315     #endif
316     }
317    
318     // filling interaction blocks with pointers
319     InteractionData ForceMatrixDecomposition::fillInteractionData(int atom1, int atom2) {
320 gezelter 1567 InteractionData idat;
321 gezelter 1551
322     #ifdef IS_MPI
323     if (storageLayout_ & DataStorage::dslAmat) {
324 gezelter 1554 idat.A1 = &(atomRowData.aMat[atom1]);
325     idat.A2 = &(atomColData.aMat[atom2]);
326 gezelter 1551 }
327 gezelter 1567
328 gezelter 1551 if (storageLayout_ & DataStorage::dslElectroFrame) {
329 gezelter 1554 idat.eFrame1 = &(atomRowData.electroFrame[atom1]);
330     idat.eFrame2 = &(atomColData.electroFrame[atom2]);
331 gezelter 1551 }
332    
333     if (storageLayout_ & DataStorage::dslTorque) {
334 gezelter 1554 idat.t1 = &(atomRowData.torque[atom1]);
335     idat.t2 = &(atomColData.torque[atom2]);
336 gezelter 1551 }
337    
338     if (storageLayout_ & DataStorage::dslDensity) {
339 gezelter 1554 idat.rho1 = &(atomRowData.density[atom1]);
340     idat.rho2 = &(atomColData.density[atom2]);
341 gezelter 1551 }
342    
343     if (storageLayout_ & DataStorage::dslFunctionalDerivative) {
344 gezelter 1554 idat.dfrho1 = &(atomRowData.functionalDerivative[atom1]);
345     idat.dfrho2 = &(atomColData.functionalDerivative[atom2]);
346 gezelter 1551 }
347 gezelter 1562 #else
348     if (storageLayout_ & DataStorage::dslAmat) {
349     idat.A1 = &(snap_->atomData.aMat[atom1]);
350     idat.A2 = &(snap_->atomData.aMat[atom2]);
351     }
352    
353     if (storageLayout_ & DataStorage::dslElectroFrame) {
354     idat.eFrame1 = &(snap_->atomData.electroFrame[atom1]);
355     idat.eFrame2 = &(snap_->atomData.electroFrame[atom2]);
356     }
357    
358     if (storageLayout_ & DataStorage::dslTorque) {
359     idat.t1 = &(snap_->atomData.torque[atom1]);
360     idat.t2 = &(snap_->atomData.torque[atom2]);
361     }
362    
363     if (storageLayout_ & DataStorage::dslDensity) {
364     idat.rho1 = &(snap_->atomData.density[atom1]);
365     idat.rho2 = &(snap_->atomData.density[atom2]);
366     }
367    
368     if (storageLayout_ & DataStorage::dslFunctionalDerivative) {
369     idat.dfrho1 = &(snap_->atomData.functionalDerivative[atom1]);
370     idat.dfrho2 = &(snap_->atomData.functionalDerivative[atom2]);
371     }
372 gezelter 1551 #endif
373 gezelter 1567 return idat;
374 gezelter 1551 }
375 gezelter 1567
376 gezelter 1551 InteractionData ForceMatrixDecomposition::fillSkipData(int atom1, int atom2){
377 gezelter 1567
378 gezelter 1562 InteractionData idat;
379     #ifdef IS_MPI
380     if (storageLayout_ & DataStorage::dslElectroFrame) {
381     idat.eFrame1 = &(atomRowData.electroFrame[atom1]);
382     idat.eFrame2 = &(atomColData.electroFrame[atom2]);
383     }
384     if (storageLayout_ & DataStorage::dslTorque) {
385     idat.t1 = &(atomRowData.torque[atom1]);
386     idat.t2 = &(atomColData.torque[atom2]);
387     }
388 gezelter 1567 if (storageLayout_ & DataStorage::dslForce) {
389     idat.t1 = &(atomRowData.force[atom1]);
390     idat.t2 = &(atomColData.force[atom2]);
391     }
392     #else
393     if (storageLayout_ & DataStorage::dslElectroFrame) {
394     idat.eFrame1 = &(snap_->atomData.electroFrame[atom1]);
395     idat.eFrame2 = &(snap_->atomData.electroFrame[atom2]);
396     }
397     if (storageLayout_ & DataStorage::dslTorque) {
398     idat.t1 = &(snap_->atomData.torque[atom1]);
399     idat.t2 = &(snap_->atomData.torque[atom2]);
400     }
401     if (storageLayout_ & DataStorage::dslForce) {
402     idat.t1 = &(snap_->atomData.force[atom1]);
403     idat.t2 = &(snap_->atomData.force[atom2]);
404     }
405     #endif
406 gezelter 1562
407 gezelter 1551 }
408 gezelter 1567
409 gezelter 1551 SelfData ForceMatrixDecomposition::fillSelfData(int atom1) {
410 gezelter 1567 SelfData sdat;
411     // Still Missing atype, skippedCharge, potVec pot,
412     if (storageLayout_ & DataStorage::dslElectroFrame) {
413     sdat.eFrame = &(snap_->atomData.electroFrame[atom1]);
414     }
415    
416     if (storageLayout_ & DataStorage::dslTorque) {
417     sdat.t = &(snap_->atomData.torque[atom1]);
418     }
419    
420     if (storageLayout_ & DataStorage::dslDensity) {
421     sdat.rho = &(snap_->atomData.density[atom1]);
422     }
423    
424     if (storageLayout_ & DataStorage::dslFunctional) {
425     sdat.frho = &(snap_->atomData.functional[atom1]);
426     }
427    
428     if (storageLayout_ & DataStorage::dslFunctionalDerivative) {
429     sdat.dfrhodrho = &(snap_->atomData.functionalDerivative[atom1]);
430     }
431    
432     return sdat;
433 gezelter 1551 }
434    
435 gezelter 1562
436 gezelter 1567
437 gezelter 1562 /*
438     * buildNeighborList
439     *
440     * first element of pair is row-indexed CutoffGroup
441     * second element of pair is column-indexed CutoffGroup
442     */
443 gezelter 1567 vector<pair<int, int> > ForceMatrixDecomposition::buildNeighborList() {
444    
445     vector<pair<int, int> > neighborList;
446     #ifdef IS_MPI
447     CellListRow.clear();
448     CellListCol.clear();
449     #else
450     CellList.clear();
451     #endif
452 gezelter 1562
453 gezelter 1567 // dangerous to not do error checking.
454     RealType skinThickness_ = info_->getSimParams()->getSkinThickness();
455     RealType rCut_;
456    
457     RealType rList_ = (rCut_ + skinThickness_);
458     RealType rl2 = rList_ * rList_;
459     Snapshot* snap_ = sman_->getCurrentSnapshot();
460 gezelter 1562 Mat3x3d Hmat = snap_->getHmat();
461     Vector3d Hx = Hmat.getColumn(0);
462     Vector3d Hy = Hmat.getColumn(1);
463     Vector3d Hz = Hmat.getColumn(2);
464 gezelter 1567 Vector3i nCells;
465 gezelter 1562
466     nCells.x() = (int) ( Hx.length() )/ rList_;
467     nCells.y() = (int) ( Hy.length() )/ rList_;
468     nCells.z() = (int) ( Hz.length() )/ rList_;
469    
470 gezelter 1567 Mat3x3d invHmat = snap_->getInvHmat();
471     Vector3d rs, scaled, dr;
472     Vector3i whichCell;
473     int cellIndex;
474    
475     #ifdef IS_MPI
476     for (int i = 0; i < nGroupsInRow_; i++) {
477 gezelter 1562 rs = cgRowData.position[i];
478 gezelter 1567 // scaled positions relative to the box vectors
479     scaled = invHmat * rs;
480     // wrap the vector back into the unit box by subtracting integer box
481     // numbers
482     for (int j = 0; j < 3; j++)
483     scaled[j] -= roundMe(scaled[j]);
484    
485     // find xyz-indices of cell that cutoffGroup is in.
486     whichCell.x() = nCells.x() * scaled.x();
487     whichCell.y() = nCells.y() * scaled.y();
488     whichCell.z() = nCells.z() * scaled.z();
489    
490     // find single index of this cell:
491     cellIndex = Vlinear(whichCell, nCells);
492     // add this cutoff group to the list of groups in this cell;
493     CellListRow[cellIndex].push_back(i);
494 gezelter 1562 }
495    
496 gezelter 1567 for (int i = 0; i < nGroupsInCol_; i++) {
497     rs = cgColData.position[i];
498     // scaled positions relative to the box vectors
499     scaled = invHmat * rs;
500     // wrap the vector back into the unit box by subtracting integer box
501     // numbers
502     for (int j = 0; j < 3; j++)
503     scaled[j] -= roundMe(scaled[j]);
504    
505     // find xyz-indices of cell that cutoffGroup is in.
506     whichCell.x() = nCells.x() * scaled.x();
507     whichCell.y() = nCells.y() * scaled.y();
508     whichCell.z() = nCells.z() * scaled.z();
509    
510     // find single index of this cell:
511     cellIndex = Vlinear(whichCell, nCells);
512     // add this cutoff group to the list of groups in this cell;
513     CellListCol[cellIndex].push_back(i);
514 gezelter 1562 }
515 gezelter 1567 #else
516     for (int i = 0; i < nGroups_; i++) {
517     rs = snap_->cgData.position[i];
518     // scaled positions relative to the box vectors
519     scaled = invHmat * rs;
520     // wrap the vector back into the unit box by subtracting integer box
521     // numbers
522     for (int j = 0; j < 3; j++)
523     scaled[j] -= roundMe(scaled[j]);
524    
525     // find xyz-indices of cell that cutoffGroup is in.
526     whichCell.x() = nCells.x() * scaled.x();
527     whichCell.y() = nCells.y() * scaled.y();
528     whichCell.z() = nCells.z() * scaled.z();
529    
530     // find single index of this cell:
531     cellIndex = Vlinear(whichCell, nCells);
532     // add this cutoff group to the list of groups in this cell;
533     CellList[cellIndex].push_back(i);
534     }
535     #endif
536    
537    
538    
539     for (int m1z = 0; m1z < nCells.z(); m1z++) {
540     for (int m1y = 0; m1y < nCells.y(); m1y++) {
541     for (int m1x = 0; m1x < nCells.x(); m1x++) {
542 gezelter 1562 Vector3i m1v(m1x, m1y, m1z);
543 gezelter 1567 int m1 = Vlinear(m1v, nCells);
544     for (int offset = 0; offset < nOffset_; offset++) {
545     Vector3i m2v = m1v + cellOffsets_[offset];
546 gezelter 1562
547 gezelter 1567 if (m2v.x() >= nCells.x()) {
548 gezelter 1562 m2v.x() = 0;
549     } else if (m2v.x() < 0) {
550 gezelter 1567 m2v.x() = nCells.x() - 1;
551 gezelter 1562 }
552    
553 gezelter 1567 if (m2v.y() >= nCells.y()) {
554 gezelter 1562 m2v.y() = 0;
555     } else if (m2v.y() < 0) {
556 gezelter 1567 m2v.y() = nCells.y() - 1;
557 gezelter 1562 }
558    
559 gezelter 1567 if (m2v.z() >= nCells.z()) {
560     m2v.z() = 0;
561     } else if (m2v.z() < 0) {
562     m2v.z() = nCells.z() - 1;
563     }
564    
565     int m2 = Vlinear (m2v, nCells);
566    
567     #ifdef IS_MPI
568     for (vector<int>::iterator j1 = CellListRow[m1].begin();
569     j1 != CellListRow[m1].end(); ++j1) {
570     for (vector<int>::iterator j2 = CellListCol[m2].begin();
571     j2 != CellListCol[m2].end(); ++j2) {
572    
573     // Always do this if we're in different cells or if
574     // we're in the same cell and the global index of the
575     // j2 cutoff group is less than the j1 cutoff group
576    
577     if (m2 != m1 || cgColToGlobal[(*j2)] < cgRowToGlobal[(*j1)]) {
578     dr = cgColData.position[(*j2)] - cgRowData.position[(*j1)];
579     snap_->wrapVector(dr);
580     if (dr.lengthSquare() < rl2) {
581     neighborList.push_back(make_pair((*j1), (*j2)));
582 gezelter 1562 }
583     }
584     }
585     }
586 gezelter 1567 #else
587     for (vector<int>::iterator j1 = CellList[m1].begin();
588     j1 != CellList[m1].end(); ++j1) {
589     for (vector<int>::iterator j2 = CellList[m2].begin();
590     j2 != CellList[m2].end(); ++j2) {
591    
592     // Always do this if we're in different cells or if
593     // we're in the same cell and the global index of the
594     // j2 cutoff group is less than the j1 cutoff group
595    
596     if (m2 != m1 || (*j2) < (*j1)) {
597     dr = snap_->cgData.position[(*j2)] - snap_->cgData.position[(*j1)];
598     snap_->wrapVector(dr);
599     if (dr.lengthSquare() < rl2) {
600     neighborList.push_back(make_pair((*j1), (*j2)));
601     }
602     }
603     }
604     }
605     #endif
606 gezelter 1562 }
607     }
608     }
609     }
610 gezelter 1567 return neighborList;
611 gezelter 1562 }
612 gezelter 1539 } //end namespace OpenMD