Intrepid
Intrepid_HCURL_TET_In_FEMDef.hpp
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43 
50 namespace Intrepid {
51 
52  template<class Scalar, class ArrayScalar>
54  const EPointType pointType ):
55  Phis_( n ),
56  coeffs_( (n+1)*(n+2)*(n+3)/2 , n*(n+2)*(n+3)/2 )
57  {
58  const int N = n*(n+2)*(n+3)/2;
59  this -> basisCardinality_ = N;
60  this -> basisDegree_ = n;
61  this -> basisCellTopology_ = shards::CellTopology(shards::getCellTopologyData<shards::Tetrahedron<4> >() );
62  this -> basisType_ = BASIS_FEM_FIAT;
63  this -> basisCoordinates_ = COORDINATES_CARTESIAN;
64  this -> basisTagsAreSet_ = false;
65 
66  const int littleN = n*(n+1)*(n+2)/2; // dim of (P_{n-1})^3 -- smaller space
67  const int bigN = (n+1)*(n+2)*(n+3)/2; // dim of (P_{n})^3 -- larger space
68  const int start_PkH = (n-1)*n*(n+1)/6; // dim of P({n-2}), offset into
69  const int dim_PkH = n*(n+1)*(n+2)/6 - start_PkH;
70  const int scalarLittleN = littleN/3;
71  const int scalarBigN = bigN/3;
72 
73  // first, need to project the basis for Nedelec space onto the
74  // orthogonal basis of degree n
75  // get coefficients of PkHx
76 
77  Teuchos::SerialDenseMatrix<int,Scalar> V1(bigN, littleN + 3 * dim_PkH);
78 
79  // these two loops get the first three sets of basis functions
80  for (int i=0;i<scalarLittleN;i++) {
81  for (int k=0;k<3;k++) {
82  V1(i+k*scalarBigN,i+k*scalarLittleN) = 1.0;
83  }
84  }
85 
86  // first 3*scalarLittleN columns are (P_{n-1})^3 space
87 
88 
89  // now I need to integrate { (x,y,z) \times } against the big basis
90  // first, get a cubature rule.
92  FieldContainer<Scalar> cubPoints( myCub.getNumPoints() , 3 );
93  FieldContainer<Scalar> cubWeights( myCub.getNumPoints() );
94  myCub.getCubature( cubPoints , cubWeights );
95 
96  // tabulate the scalar orthonormal basis at cubature points
97  FieldContainer<Scalar> phisAtCubPoints( scalarBigN , myCub.getNumPoints() );
98  Phis_.getValues( phisAtCubPoints , cubPoints , OPERATOR_VALUE );
99 
100 
101 
102  // first set of these functions will write into the first dimPkH columns of remainder
103 
104  for (int j=0;j<dim_PkH;j++) { // loop over homogeneous polynomials
105  // write into second spatial component, where
106  // I integrate z phi_j phi_i
107  for (int i=0;i<scalarBigN;i++) {
108  V1(scalarBigN+i,littleN+j) = 0.0;
109  for (int k=0;k<myCub.getNumPoints();k++) {
110  V1(scalarBigN+i,littleN+j) -= cubWeights(k) * cubPoints(k,2)
111  * phisAtCubPoints(start_PkH+j,k)
112  * phisAtCubPoints(i,k);
113  }
114  }
115  // write into third spatial component (-y phi_j, phi_i)
116  for (int i=0;i<scalarBigN;i++) {
117  V1(2*scalarBigN+i,littleN+j) = 0.0;
118  for (int k=0;k<myCub.getNumPoints();k++) {
119  V1(2*scalarBigN+i,littleN+j) += cubWeights(k) * cubPoints(k,1)
120  * phisAtCubPoints(start_PkH+j,k)
121  * phisAtCubPoints(i,k);
122  }
123  }
124  }
125 
126  // second set of basis functions, write into second set of dimPkH columns
127  for (int j=0;j<dim_PkH;j++) { // loop over homogeneous polynomials
128  // write into first spatial component, where
129  // I integrate -z phi_j phi_i
130  for (int i=0;i<scalarBigN;i++) {
131  V1(i,littleN+dim_PkH+j) = 0.0;
132  for (int k=0;k<myCub.getNumPoints();k++) {
133  V1(i,littleN+dim_PkH+j) += cubWeights(k) * cubPoints(k,2)
134  * phisAtCubPoints(start_PkH+j,k)
135  * phisAtCubPoints(i,k);
136  }
137  }
138 
139  // third spatial component, x phi_j phi_i
140  for (int i=0;i<scalarBigN;i++) {
141  V1(2*scalarBigN+i,littleN+dim_PkH+j) = 0.0;
142  for (int k=0;k<myCub.getNumPoints();k++) {
143  V1(2*scalarBigN+i,littleN+dim_PkH+j) -= cubWeights(k) * cubPoints(k,0)
144  * phisAtCubPoints(start_PkH+j,k)
145  * phisAtCubPoints(i,k);
146  }
147  }
148  }
149 
150  // third clump of dimPkH columns
151  for (int j=0;j<dim_PkH;j++) { // loop over homogeneous polynomials
152  // write into first spatial component, where
153  // I integrate y phi_j phi_i
154  for (int i=0;i<scalarBigN;i++) {
155  V1(i,littleN+2*dim_PkH+j) = 0.0;
156  for (int k=0;k<myCub.getNumPoints();k++) {
157  V1(i,littleN+2*dim_PkH+j) -= cubWeights(k) * cubPoints(k,1)
158  * phisAtCubPoints(start_PkH+j,k)
159  * phisAtCubPoints(i,k);
160  }
161  }
162  // second spatial component, -x phi_j phi_i
163  for (int i=0;i<scalarBigN;i++) {
164  V1(scalarBigN+i,littleN+2*dim_PkH+j) = 0.0;
165  for (int k=0;k<myCub.getNumPoints();k++) {
166  V1(scalarBigN+i,littleN+2*dim_PkH+j) += cubWeights(k) * cubPoints(k,0)
167  * phisAtCubPoints(start_PkH+j,k)
168  * phisAtCubPoints(i,k);
169  }
170  }
171  }
172 
173  // now I need to set up an SVD to get a basis for the space
174  Teuchos::SerialDenseMatrix<int,Scalar> S(bigN,1);
175  Teuchos::SerialDenseMatrix<int,Scalar> U(bigN, bigN);
176  Teuchos::SerialDenseMatrix<int,Scalar> Vt(bigN,bigN);
177  Teuchos::SerialDenseMatrix<int,Scalar> work(5*bigN,1);
178  Teuchos::SerialDenseMatrix<int,Scalar> rWork(1,1);
179  int info;
180 
181  Teuchos::LAPACK<int,Scalar> lala;
182 
183  lala.GESVD( 'A',
184  'N',
185  V1.numRows() ,
186  V1.numCols() ,
187  V1.values() ,
188  V1.stride() ,
189  S.values() ,
190  U.values() ,
191  U.stride() ,
192  Vt.values() ,
193  Vt.stride() ,
194  work.values() ,
195  5*bigN ,
196  rWork.values() ,
197  &info );
198 
199  int num_nonzero_sv = 0;
200  for (int i=0;i<bigN;i++) {
201  if (S(i,0) > INTREPID_TOL) {
202  num_nonzero_sv++;
203  }
204  }
205 
206  Teuchos::SerialDenseMatrix<int,Scalar> Uslender(bigN, num_nonzero_sv);
207  for (int j=0;j<num_nonzero_sv;j++) {
208  for (int i=0;i<bigN;i++) {
209  Uslender(i,j) = U(i,j);
210  }
211  }
212 
213  // apply nodes to big space
214  Teuchos::SerialDenseMatrix<int,Scalar> V2(N, bigN);
215 
216  shards::CellTopology edgeTop(shards::getCellTopologyData<shards::Line<2> >() );
217  shards::CellTopology faceTop(shards::getCellTopologyData<shards::Triangle<3> >() );
218 
219 
220  const int numPtsPerEdge = PointTools::getLatticeSize( edgeTop ,
221  n+1 ,
222  1 );
223 
224  const int numPtsPerFace = PointTools::getLatticeSize( faceTop ,
225  n+1 ,
226  1 );
227 
228  const int numPtsPerCell = PointTools::getLatticeSize( this->basisCellTopology_ ,
229  n+1 ,
230  1 );
231 
232  // these hold the reference domain points that will be mapped to each edge or face
233  FieldContainer<Scalar> oneDPts( numPtsPerEdge , 1 );
234  FieldContainer<Scalar> twoDPts( numPtsPerFace , 2 );
235 
236  if (pointType == POINTTYPE_WARPBLEND) {
237  CubatureDirectLineGauss<Scalar> edgeRule( numPtsPerEdge );
238  FieldContainer<Scalar> edgeCubWts( numPtsPerEdge );
239  edgeRule.getCubature( oneDPts , edgeCubWts );
240  }
241  else if (pointType == POINTTYPE_EQUISPACED ) {
242  PointTools::getLattice<Scalar,FieldContainer<Scalar> >( oneDPts ,
243  edgeTop ,
244  n+1 ,
245  1 ,
246  pointType );
247  }
248 
249  PointTools::getLattice<Scalar,FieldContainer<Scalar> >( twoDPts ,
250  faceTop ,
251  n+1 ,
252  1 ,
253  pointType );
254 
255  FieldContainer<Scalar> edgePts( numPtsPerEdge , 3 );
256  FieldContainer<Scalar> phisAtEdgePoints( scalarBigN , numPtsPerEdge );
257 
258  FieldContainer<Scalar> facePts( numPtsPerFace , 3 );
259  FieldContainer<Scalar> phisAtFacePoints( scalarBigN ,
260  numPtsPerFace );
261 
262  FieldContainer<Scalar> edgeTan( 3 );
263 
264  // loop over the edges
265  for (int edge=0;edge<6;edge++) {
267  edge ,
268  this->basisCellTopology_ );
269  /* multiply by 2.0 to account for a scaling in Pavel's definition */
270  for (int j=0;j<3;j++) {
271  edgeTan(j) *= 2.0;
272  }
273 
275  oneDPts ,
276  1 ,
277  edge ,
278  this->basisCellTopology_ );
279 
280  Phis_.getValues( phisAtEdgePoints , edgePts , OPERATOR_VALUE );
281 
282  // loop over points (rows of V2)
283  for (int j=0;j<numPtsPerEdge;j++) {
284  // loop over orthonormal basis functions (columns of V2)
285  for (int k=0;k<scalarBigN;k++) {
286  for (int d=0;d<3;d++) {
287  V2(edge*numPtsPerEdge+j,k+scalarBigN*d) = edgeTan(d) * phisAtEdgePoints(k,j);
288  }
289  }
290  }
291  }
292 
293  // handle the faces, if needed
294  if (n > 1) {
295  FieldContainer<Scalar> refFaceTanU(3);
296  FieldContainer<Scalar> refFaceTanV(3);
297  for (int face=0;face<4;face++) {
299  refFaceTanV ,
300  face ,
301  this->basisCellTopology_ );
303  twoDPts ,
304  2 ,
305  face ,
306  this->basisCellTopology_ );
307  Phis_.getValues( phisAtFacePoints , facePts , OPERATOR_VALUE );
308  for (int j=0;j<numPtsPerFace;j++) {
309  for (int k=0;k<scalarBigN;k++) {
310  for (int d=0;d<3;d++) {
311  V2(6*numPtsPerEdge+2*face*numPtsPerFace+2*j,k+scalarBigN*d) =
312  refFaceTanU(d) * phisAtFacePoints(k,j);
313  V2(6*numPtsPerEdge+2*face*numPtsPerFace+2*j+1,k+scalarBigN*d) =
314  refFaceTanV(d) * phisAtFacePoints(k,j);
315  }
316  }
317  }
318  }
319  }
320 
321  // internal dof, if needed
322  if (n > 2) {
323  FieldContainer<Scalar> cellPoints( numPtsPerCell , 3 );
324  PointTools::getLattice<Scalar,FieldContainer<Scalar> >( cellPoints ,
325  this->getBaseCellTopology() ,
326  n + 1 ,
327  1 ,
328  pointType );
329  FieldContainer<Scalar> phisAtCellPoints( scalarBigN , numPtsPerCell );
330  Phis_.getValues( phisAtCellPoints , cellPoints , OPERATOR_VALUE );
331  for (int i=0;i<numPtsPerCell;i++) {
332  for (int j=0;j<scalarBigN;j++) {
333  for (int k=0;k<3;k++) {
334  V2(6*numPtsPerEdge+8*numPtsPerFace+k*numPtsPerCell+i,k*scalarBigN+j) = phisAtCellPoints(j,i);
335  }
336  }
337  }
338  }
339 
340  Teuchos::SerialDenseMatrix<int,Scalar> Vsdm( N , N );
341 
342  // multiply V2 * U --> V
343  Vsdm.multiply( Teuchos::NO_TRANS , Teuchos::NO_TRANS , 1.0 , V2 , Uslender , 0.0 );
344 
345  Teuchos::SerialDenseSolver<int,Scalar> solver;
346  solver.setMatrix( rcp( &Vsdm , false ) );
347 
348  solver.invert( );
349 
350 
351  Teuchos::SerialDenseMatrix<int,Scalar> Csdm( bigN , N );
352  Csdm.multiply( Teuchos::NO_TRANS , Teuchos::NO_TRANS , 1.0 , Uslender , Vsdm , 0.0 );
353 
354  //std::cout << Csdm << "\n";
355 
356  for (int i=0;i<bigN;i++) {
357  for (int j=0;j<N;j++) {
358  coeffs_(i,j) = Csdm(i,j);
359  }
360  }
361 
362  //std::cout << coeffs_ << std::endl;
363 
364  }
365 
366  template<class Scalar, class ArrayScalar>
368  // Basis-dependent initializations
369  int tagSize = 4; // size of DoF tag, i.e., number of fields in the tag
370  int posScDim = 0; // position in the tag, counting from 0, of the subcell dim
371  int posScOrd = 1; // position in the tag, counting from 0, of the subcell ordinal
372  int posDfOrd = 2; // position in the tag, counting from 0, of DoF ordinal relative to the subcell
373 
374  // An array with local DoF tags assigned to the basis functions, in the order of their local enumeration
375 
376  int *tags = new int[ tagSize * this->getCardinality() ];
377  int *tag_cur = tags;
378  const int deg = this->getDegree();
379 
380  shards::CellTopology edgeTop(shards::getCellTopologyData<shards::Line<2> >() );
381  shards::CellTopology faceTop(shards::getCellTopologyData<shards::Triangle<3> >() );
382 
383 
384  const int numPtsPerEdge = PointTools::getLatticeSize( edgeTop ,
385  deg+1 ,
386  1 );
387 
388  const int numPtsPerFace = PointTools::getLatticeSize( faceTop ,
389  deg+1 ,
390  1 );
391 
392  const int numPtsPerCell = PointTools::getLatticeSize( this->basisCellTopology_ ,
393  deg+1 ,
394  1 );
395 
396  // edge dof first
397  for (int e=0;e<6;e++) {
398  for (int i=0;i<numPtsPerEdge;i++) {
399  tag_cur[0] = 1; tag_cur[1] = e; tag_cur[2] = i; tag_cur[3] = numPtsPerEdge;
400  tag_cur += tagSize;
401  }
402  }
403 
404  // face dof, 2 * numPtsPerFace dof per face
405  for (int f=0;f<4;f++) {
406  for (int i=0;i<2*numPtsPerFace;i++) {
407  tag_cur[0] = 2; tag_cur[1] = f; tag_cur[2] = i; tag_cur[3] = 2*numPtsPerFace;
408  tag_cur+= tagSize;
409  }
410  }
411 
412  // internal dof, 3 * numPtsPerCell
413  for (int i=0;i<3*numPtsPerCell;i++) {
414  tag_cur[0] = 3; tag_cur[1] = 0; tag_cur[2] = i; tag_cur[3] = 3*numPtsPerCell;
415  tag_cur += tagSize;
416  }
417  Intrepid::setOrdinalTagData(this -> tagToOrdinal_,
418  this -> ordinalToTag_,
419  tags,
420  this -> basisCardinality_,
421  tagSize,
422  posScDim,
423  posScOrd,
424  posDfOrd);
425 
426  delete []tags;
427 
428  }
429 
430 
431 
432  template<class Scalar, class ArrayScalar>
434  const ArrayScalar & inputPoints,
435  const EOperator operatorType) const {
436 
437  // Verify arguments
438 #ifdef HAVE_INTREPID_DEBUG
439  Intrepid::getValues_HCURL_Args<Scalar, ArrayScalar>(outputValues,
440  inputPoints,
441  operatorType,
442  this -> getBaseCellTopology(),
443  this -> getCardinality() );
444 #endif
445  const int numPts = inputPoints.dimension(0);
446  const int deg = this -> getDegree();
447  const int scalarBigN = (deg+1)*(deg+2)*(deg+3)/6;
448 
449  try {
450  switch (operatorType) {
451  case OPERATOR_VALUE:
452  {
453  FieldContainer<Scalar> phisCur( scalarBigN , numPts );
454  Phis_.getValues( phisCur , inputPoints , OPERATOR_VALUE );
455 
456  for (int i=0;i<outputValues.dimension(0);i++) { // RT bf
457  for (int j=0;j<outputValues.dimension(1);j++) { // point
458  for (int d=0;d<3;d++) {
459  outputValues(i,j,d) = 0.0;
460  }
461  for (int k=0;k<scalarBigN;k++) { // Dubiner bf
462  for (int d=0;d<3;d++) {
463  outputValues(i,j,d) += coeffs_(k+d*scalarBigN,i) * phisCur(k,j);
464  }
465  }
466  }
467  }
468  }
469  break;
470  case OPERATOR_CURL:
471  {
472  FieldContainer<Scalar> phisCur( scalarBigN , numPts , 3 );
473  Phis_.getValues( phisCur , inputPoints , OPERATOR_GRAD );
474  for (int i=0;i<outputValues.dimension(0);i++) { // bf loop
475  for (int j=0;j<outputValues.dimension(1);j++) { // point loop
476  outputValues(i,j,0) = 0.0;
477  for (int k=0;k<scalarBigN;k++) {
478  outputValues(i,j,0) += coeffs_(k+2*scalarBigN,i) * phisCur(k,j,1);
479  outputValues(i,j,0) -= coeffs_(k+scalarBigN,i) * phisCur(k,j,2);
480  }
481 
482  outputValues(i,j,1) = 0.0;
483  for (int k=0;k<scalarBigN;k++) {
484  outputValues(i,j,1) += coeffs_(k,i) * phisCur(k,j,2);
485  outputValues(i,j,1) -= coeffs_(k+2*scalarBigN,i) * phisCur(k,j,0);
486  }
487 
488  outputValues(i,j,2) = 0.0;
489  for (int k=0;k<scalarBigN;k++) {
490  outputValues(i,j,2) += coeffs_(k+scalarBigN,i) * phisCur(k,j,0);
491  outputValues(i,j,2) -= coeffs_(k,i) * phisCur(k,j,1);
492  }
493  }
494  }
495  }
496  break;
497  default:
498  TEUCHOS_TEST_FOR_EXCEPTION( true , std::invalid_argument,
499  ">>> ERROR (Basis_HCURL_TET_In_FEM): Operator type not implemented");
500  break;
501  }
502  }
503  catch (std::invalid_argument &exception){
504  TEUCHOS_TEST_FOR_EXCEPTION( true , std::invalid_argument,
505  ">>> ERROR (Basis_HCURL_TET_In_FEM): Operator type not implemented");
506  }
507 
508  }
509 
510 
511 
512  template<class Scalar, class ArrayScalar>
514  const ArrayScalar & inputPoints,
515  const ArrayScalar & cellVertices,
516  const EOperator operatorType) const {
517  TEUCHOS_TEST_FOR_EXCEPTION( (true), std::logic_error,
518  ">>> ERROR (Basis_HCURL_TET_In_FEM): FEM Basis calling an FVD member function");
519  }
520 
521 
522 }// namespace Intrepid
Basis_HCURL_TET_In_FEM(const int n, const EPointType pointType)
Constructor.
static void getReferenceEdgeTangent(ArrayEdgeTangent &refEdgeTangent, const int &edgeOrd, const shards::CellTopology &parentCell)
Computes constant tangent vectors to edges of 2D or 3D reference cells.
static void mapToReferenceSubcell(ArraySubcellPoint &refSubcellPoints, const ArrayParamPoint &paramPoints, const int subcellDim, const int subcellOrd, const shards::CellTopology &parentCell)
Computes parameterization maps of 1- and 2-subcells of reference cells.
virtual void initializeTags()
Initializes tagToOrdinal_ and ordinalToTag_ lookup arrays.
virtual void getCubature(ArrayPoint &cubPoints, ArrayWeight &cubWeights) const
Returns cubature points and weights (return arrays must be pre-sized/pre-allocated).
Defines Gauss integration rules on a line.
EBasis basisType_
Type of the basis.
static void getReferenceFaceTangents(ArrayFaceTangentU &refFaceTanU, ArrayFaceTangentV &refFaceTanV, const int &faceOrd, const shards::CellTopology &parentCell)
Computes pairs of constant tangent vectors to faces of a 3D reference cells.
Defines direct integration rules on a tetrahedron.
bool basisTagsAreSet_
&quot;true&quot; if tagToOrdinal_ and ordinalToTag_ have been initialized
virtual int getNumPoints() const
Returns the number of cubature points.
ECoordinates basisCoordinates_
The coordinate system for which the basis is defined.
shards::CellTopology basisCellTopology_
Base topology of the cells for which the basis is defined. See the Shards package http://trilinos...
virtual const shards::CellTopology getBaseCellTopology() const
Returns the base cell topology for which the basis is defined. See Shards documentation http://trilin...
FieldContainer< Scalar > coeffs_
Array holding the expansion coefficients of the nodal basis in terms of Phis_.
void getValues(ArrayScalar &outputValues, const ArrayScalar &inputPoints, const EOperator operatorType) const
Evaluation of a FEM basis on a reference Tetrahedron cell.
int basisDegree_
Degree of the largest complete polynomial space that can be represented by the basis.
int basisCardinality_
Cardinality of the basis, i.e., the number of basis functions/degrees-of-freedom. ...
static int getLatticeSize(const shards::CellTopology &cellType, const int order, const int offset=0)
Computes the number of points in a lattice of a given order on a simplex (currently disabled for othe...
Basis_HGRAD_TET_Cn_FEM_ORTH< Scalar, FieldContainer< Scalar > > Phis_
Orthogonal basis of ofder n, in terms of which the H(curl) basis functions are expressed.