Reference documentation for deal.II version Git ca0b05a7a7 2020-12-01 11:49:21 -0500
polynomials_bdm.cc
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15
16
21
22 #include <iomanip>
23 #include <iostream>
24 #include <memory>
25
27
28
29 template <int dim>
31  : TensorPolynomialsBase<dim>(k + 1, n_polynomials(k))
32  , polynomial_space(Polynomials::Legendre::generate_complete_basis(k))
33  , monomials((dim == 2) ? (1) : (k + 2))
34  , p_values(polynomial_space.n())
37 {
38  switch (dim)
39  {
40  case 2:
42  break;
43  case 3:
44  for (unsigned int i = 0; i < monomials.size(); ++i)
46  break;
47  default:
48  Assert(false, ExcNotImplemented());
49  }
50 }
51
52
53
54 template <int dim>
55 void
57  const Point<dim> & unit_point,
58  std::vector<Tensor<1, dim>> &values,
61  std::vector<Tensor<4, dim>> &third_derivatives,
62  std::vector<Tensor<5, dim>> &fourth_derivatives) const
63 {
64  Assert(values.size() == this->n() || values.size() == 0,
65  ExcDimensionMismatch(values.size(), this->n()));
70  Assert(third_derivatives.size() == this->n() || third_derivatives.size() == 0,
71  ExcDimensionMismatch(third_derivatives.size(), this->n()));
72  Assert(fourth_derivatives.size() == this->n() ||
73  fourth_derivatives.size() == 0,
74  ExcDimensionMismatch(fourth_derivatives.size(), this->n()));
75
76  // third and fourth derivatives not implemented
77  (void)third_derivatives;
78  Assert(third_derivatives.size() == 0, ExcNotImplemented());
79  (void)fourth_derivatives;
80  Assert(fourth_derivatives.size() == 0, ExcNotImplemented());
81
82  const unsigned int n_sub = polynomial_space.n();
83
85  // arrays in the following block
86  // using a mutex to make sure they
87  // are not used by multiple threads
88  // at once
89  {
90  std::lock_guard<std::mutex> lock(mutex);
91
92  p_values.resize((values.size() == 0) ? 0 : n_sub);
95
96  // Compute values of complete space
97  // and insert into tensors. Result
98  // will have first all polynomials
99  // in the x-component, then y and
100  // z.
101  polynomial_space.evaluate(unit_point,
102  p_values,
107
108  std::fill(values.begin(), values.end(), Tensor<1, dim>());
109  for (unsigned int i = 0; i < p_values.size(); ++i)
110  for (unsigned int j = 0; j < dim; ++j)
111  values[i + j * n_sub][j] = p_values[i];
112
114  for (unsigned int i = 0; i < p_grads.size(); ++i)
115  for (unsigned int j = 0; j < dim; ++j)
117
120  for (unsigned int j = 0; j < dim; ++j)
122  }
123
124  // This is the first polynomial not
125  // covered by the P_k subspace
126  unsigned int start = dim * n_sub;
127
128  // Store values of auxiliary
129  // polynomials and their three
130  // derivatives
131  std::vector<std::vector<double>> monovali(dim, std::vector<double>(4));
132  std::vector<std::vector<double>> monovalk(dim, std::vector<double>(4));
133
134  if (dim == 2)
135  {
136  for (unsigned int d = 0; d < dim; ++d)
137  monomials[0].value(unit_point(d), monovali[d]);
138  if (values.size() != 0)
139  {
140  values[start][0] = monovali[0][0];
141  values[start][1] = -unit_point(1) * monovali[0][1];
142  values[start + 1][0] = unit_point(0) * monovali[1][1];
143  values[start + 1][1] = -monovali[1][0];
144  }
146  {
149  grads[start][1][0] = -unit_point(1) * monovali[0][2];
151  grads[start + 1][0][0] = monovali[1][1];
152  grads[start + 1][0][1] = unit_point(0) * monovali[1][2];
153  grads[start + 1][1][0] = 0.;
154  grads[start + 1][1][1] = -monovali[1][1];
155  }
157  {
174  }
175  }
176  else // dim == 3
177  {
178  // The number of curls in each
179  // component. Note that the
180  // table in BrezziFortin91 has
181  // a typo, but the text has the
182  // right basis
183
184  // Note that the next basis
185  // function is always obtained
186  // from the previous by cyclic
187  // rotation of the coordinates
188  const unsigned int n_curls = monomials.size() - 1;
189  for (unsigned int i = 0; i < n_curls; ++i, start += dim)
190  {
191  for (unsigned int d = 0; d < dim; ++d)
192  {
193  // p(t) = t^(i+1)
194  monomials[i + 1].value(unit_point(d), monovali[d]);
195  // q(t) = t^(k-i)
196  monomials[this->degree() - 1 - i].value(unit_point(d),
197  monovalk[d]);
198  }
199  if (values.size() != 0)
200  {
201  // x p'(y) q(z)
202  values[start][0] =
203  unit_point(0) * monovali[1][1] * monovalk[2][0];
204  // - p(y) q(z)
205  values[start][1] = -monovali[1][0] * monovalk[2][0];
206  values[start][2] = 0.;
207
208  // y p'(z) q(x)
209  values[start + 1][1] =
210  unit_point(1) * monovali[2][1] * monovalk[0][0];
211  // - p(z) q(x)
212  values[start + 1][2] = -monovali[2][0] * monovalk[0][0];
213  values[start + 1][0] = 0.;
214
215  // z p'(x) q(y)
216  values[start + 2][2] =
217  unit_point(2) * monovali[0][1] * monovalk[1][0];
218  // -p(x) q(y)
219  values[start + 2][0] = -monovali[0][0] * monovalk[1][0];
220  values[start + 2][1] = 0.;
221  }
223  {
224  grads[start][0][0] = monovali[1][1] * monovalk[2][0];
226  unit_point(0) * monovali[1][2] * monovalk[2][0];
228  unit_point(0) * monovali[1][1] * monovalk[2][1];
230  grads[start][1][1] = -monovali[1][1] * monovalk[2][0];
231  grads[start][1][2] = -monovali[1][0] * monovalk[2][1];
235
236  grads[start + 1][1][1] = monovali[2][1] * monovalk[0][0];
238  unit_point(1) * monovali[2][2] * monovalk[0][0];
240  unit_point(1) * monovali[2][1] * monovalk[0][1];
241  grads[start + 1][2][1] = 0.;
242  grads[start + 1][2][2] = -monovali[2][1] * monovalk[0][0];
243  grads[start + 1][2][0] = -monovali[2][0] * monovalk[0][1];
244  grads[start + 1][0][1] = 0.;
245  grads[start + 1][0][2] = 0.;
246  grads[start + 1][0][0] = 0.;
247
248  grads[start + 2][2][2] = monovali[0][1] * monovalk[1][0];
250  unit_point(2) * monovali[0][2] * monovalk[1][0];
252  unit_point(2) * monovali[0][1] * monovalk[1][1];
253  grads[start + 2][0][2] = 0.;
254  grads[start + 2][0][0] = -monovali[0][1] * monovalk[1][0];
255  grads[start + 2][0][1] = -monovali[0][0] * monovalk[1][1];
256  grads[start + 2][1][2] = 0.;
257  grads[start + 2][1][0] = 0.;
258  grads[start + 2][1][1] = 0.;
259  }
261  {
267  unit_point(0) * monovali[1][3] * monovalk[2][0];
269  unit_point(0) * monovali[1][2] * monovalk[2][1];
272  unit_point(0) * monovali[1][2] * monovalk[2][1];
274  unit_point(0) * monovali[1][1] * monovalk[2][2];
293
304  unit_point(1) * monovali[2][1] * monovalk[0][2];
307  unit_point(1) * monovali[2][2] * monovalk[0][1];
312  unit_point(1) * monovalk[0][1] * monovali[2][2];
315  unit_point(1) * monovalk[0][0] * monovali[2][3];
325
345  unit_point(2) * monovali[0][3] * monovalk[1][0];
347  unit_point(2) * monovali[0][2] * monovalk[1][1];
350  unit_point(2) * monovali[0][2] * monovalk[1][1];
352  unit_point(2) * monovali[0][1] * monovalk[1][2];
357  }
358  }
359  Assert(start == this->n(), ExcInternalError());
360  }
361 }
362
363
364 /*
365 template <int dim>
366 void
367 PolynomialsBDM<dim>::compute_node_matrix (Table<2,double>& A) const
368 {
369  std::vector<Polynomial<double> > moment_weight(2);
370  for (unsigned int i=0;i<moment_weight.size();++i)
371  moment_weight[i] = Monomial<double>(i);
372
373  QGauss<dim-1> qface(polynomial_space.degree()+1);
374
375  std::vector<Tensor<1,dim> > values(n());
378  values.resize(n());
379
380  for (unsigned int face=0;face<2*dim;++face)
381  {
382  double orientation = 1.;
383  if ((face==0) || (face==3))
384  orientation = -1.;
385
386  for (unsigned int k=0;k<qface.size();++k)
387  {
388  const double w = qface.weight(k) * orientation;
389  const double x = qface.point(k)(0);
390  Point<dim> p;
391  switch (face)
392  {
393  case 2:
394  p(1) = 1.;
395  case 0:
396  p(0) = x;
397  break;
398  case 1:
399  p(0) = 1.;
400  case 3:
401  p(1) = x;
402  break;
403  }
404 // std::cerr << p
405 // << '\t' << moment_weight[0].value(x)
406 // << '\t' << moment_weight[1].value(x);
407
409
410  for (unsigned int i=0;i<n();++i)
411  {
412 // std::cerr << '\t' << std::setw(6) << values[i][1-face%2];
413  // Integrate normal component.
414  // This is easy on the unit
415 square for (unsigned int j=0;j<moment_weight.size();++j)
416  A(moment_weight.size()*face+j,i)
417  += w * values[i][1-face%2] * moment_weight[j].value(x);
418  }
419 // std::cerr << std::endl;
420  }
421  }
422
423  // Volume integrals are missing
424  //
425  // This degree is one larger
426  Assert (polynomial_space.degree() <= 2,
427  ExcNotImplemented());
428 }
429 */
430
431 template <int dim>
432 unsigned int
434 {
435  if (dim == 1)
436  return k + 1;
437  if (dim == 2)
438  return (k + 1) * (k + 2) + 2;
439  if (dim == 3)
440  return ((k + 1) * (k + 2) * (k + 3)) / 2 + 3 * (k + 1);
441  Assert(false, ExcNotImplemented());
442  return 0;
443 }
444
445
446 template <int dim>
447 std::unique_ptr<TensorPolynomialsBase<dim>>
449 {
450  return std::make_unique<PolynomialsBDM<dim>>(*this);
451 }
452
453
454 template class PolynomialsBDM<1>;
455 template class PolynomialsBDM<2>;
456 template class PolynomialsBDM<3>;
457
458
unsigned int degree() const
PolynomialsBDM(const unsigned int k)
virtual std::unique_ptr< TensorPolynomialsBase< dim > > clone() const override
static unsigned int n_polynomials(const unsigned int degree)
std::vector< Polynomials::Polynomial< double > > monomials
void evaluate(const Point< dim > &unit_point, std::vector< Tensor< 1, dim >> &values, std::vector< Tensor< 2, dim >> &grads, std::vector< Tensor< 3, dim >> &grad_grads, std::vector< Tensor< 4, dim >> &third_derivatives, std::vector< Tensor< 5, dim >> &fourth_derivatives) const override
std::vector< Tensor< 3, dim > > p_third_derivatives
#define Assert(cond, exc)
Definition: exceptions.h:1466
static ::ExceptionBase & ExcDimensionMismatch(std::size_t arg1, std::size_t arg2)
#define DEAL_II_NAMESPACE_CLOSE
Definition: config.h:372
std::vector< double > p_values
SymmetricTensor< 2, dim, Number > d(const Tensor< 2, dim, Number > &F, const Tensor< 2, dim, Number > &dF_dt)
std::vector< Tensor< 1, dim > > p_grads
#define DEAL_II_NAMESPACE_OPEN
Definition: config.h:371
std::vector< Tensor< 4, dim > > p_fourth_derivatives
static ::ExceptionBase & ExcNotImplemented()