Reference documentation for deal.II version Git e7bb9ce7b3 2020-09-18 12:07:32 -0400
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tridiagonal_matrix.h
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4 //
5 // This file is part of the deal.II library.
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12 // the top level directory of deal.II.
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15 
16 #ifndef dealii_tridiagonal_matrix_h
17 #define dealii_tridiagonal_matrix_h
18 
19 #include <deal.II/base/config.h>
20 
22 
24 
25 #include <iomanip>
26 #include <vector>
27 
29 
30 // forward declarations
31 #ifndef DOXYGEN
32 template <typename number>
33 class Vector;
34 #endif
35 
51 template <typename number>
53 {
54 public:
56 
57 
61 
68  TridiagonalMatrix(size_type n = 0, bool symmetric = false);
69 
74  void
75  reinit(size_type n, bool symmetric = false);
76 
77 
79 
81 
82 
87  size_type
88  m() const;
89 
94  size_type
95  n() const;
96 
102  bool
103  all_zero() const;
104 
106 
108 
109 
113  number
114  operator()(size_type i, size_type j) const;
115 
125  number &
127 
129 
131 
132 
142  void
144  const Vector<number> &v,
145  const bool adding = false) const;
146 
153  void
154  vmult_add(Vector<number> &w, const Vector<number> &v) const;
155 
165  void
167  const Vector<number> &v,
168  const bool adding = false) const;
169 
177  void
178  Tvmult_add(Vector<number> &w, const Vector<number> &v) const;
179 
185  number
186  matrix_scalar_product(const Vector<number> &u, const Vector<number> &v) const;
187 
197  number
198  matrix_norm_square(const Vector<number> &v) const;
199 
201 
203 
204 
210  void
215  number
216  eigenvalue(const size_type i) const;
218 
220 
221 
224  template <class OutputStream>
225  void
226  print(OutputStream & s,
227  const unsigned int width = 5,
228  const unsigned int precision = 2) const;
230 
231 private:
235  std::vector<number> diagonal;
245  std::vector<number> left;
251  std::vector<number> right;
252 
258 
266 };
267 
270 //---------------------------------------------------------------------------
271 #ifndef DOXYGEN
272 
273 template <typename number>
276 {
277  return diagonal.size();
278 }
279 
280 
281 
282 template <typename number>
285 {
286  return diagonal.size();
287 }
288 
289 
290 template <typename number>
291 inline number
293 {
294  AssertIndexRange(i, n());
295  AssertIndexRange(j, n());
296  Assert(i <= j + 1, ExcIndexRange(i, j - 1, j + 2));
297  Assert(j <= i + 1, ExcIndexRange(j, i - 1, i + 2));
298 
299  if (j == i)
300  return diagonal[i];
301  if (j == i - 1)
302  {
303  if (is_symmetric)
304  return right[i - 1];
305  else
306  return left[i];
307  }
308 
309  if (j == i + 1)
310  return right[i];
311 
312  Assert(false, ExcInternalError());
313  return 0;
314 }
315 
316 
317 template <typename number>
318 inline number &
320 {
321  AssertIndexRange(i, n());
322  AssertIndexRange(j, n());
323  Assert(i <= j + 1, ExcIndexRange(i, j - 1, j + 2));
324  Assert(j <= i + 1, ExcIndexRange(j, i - 1, i + 2));
325 
326  if (j == i)
327  return diagonal[i];
328  if (j == i - 1)
329  {
330  if (is_symmetric)
331  return right[i - 1];
332  else
333  return left[i];
334  }
335 
336  if (j == i + 1)
337  return right[i];
338 
339  Assert(false, ExcInternalError());
340  return diagonal[0];
341 }
342 
343 
344 template <typename number>
345 template <class OutputStream>
346 void
347 TridiagonalMatrix<number>::print(OutputStream & s,
348  const unsigned int width,
349  const unsigned int) const
350 {
351  for (size_type i = 0; i < n(); ++i)
352  {
353  if (i > 0)
354  s << std::setw(width) << (*this)(i, i - 1);
355  else
356  s << std::setw(width) << "";
357 
358  s << ' ' << (*this)(i, i) << ' ';
359 
360  if (i < n() - 1)
361  s << std::setw(width) << (*this)(i, i + 1);
362 
363  s << std::endl;
364  }
365 }
366 
367 
368 #endif // DOXYGEN
369 
371 
372 #endif
Matrix is symmetric.
std::vector< number > left
void print(OutputStream &s, const unsigned int width=5, const unsigned int precision=2) const
#define AssertIndexRange(index, range)
Definition: exceptions.h:1636
void vmult(Vector< number > &w, const Vector< number > &v, const bool adding=false) const
static ::ExceptionBase & ExcIndexRange(int arg1, int arg2, int arg3)
void Tvmult_add(Vector< number > &w, const Vector< number > &v) const
#define Assert(cond, exc)
Definition: exceptions.h:1411
std::vector< number > right
number matrix_scalar_product(const Vector< number > &u, const Vector< number > &v) const
#define DEAL_II_NAMESPACE_CLOSE
Definition: config.h:363
TridiagonalMatrix(size_type n=0, bool symmetric=false)
number matrix_norm_square(const Vector< number > &v) const
size_type n() const
number eigenvalue(const size_type i) const
void Tvmult(Vector< number > &w, const Vector< number > &v, const bool adding=false) const
Tensor< 2, dim, Number > w(const Tensor< 2, dim, Number > &F, const Tensor< 2, dim, Number > &dF_dt)
unsigned int global_dof_index
Definition: types.h:76
number operator()(size_type i, size_type j) const
#define DEAL_II_NAMESPACE_OPEN
Definition: config.h:362
LAPACKSupport::State state
std::vector< number > diagonal
size_type m() const
void reinit(size_type n, bool symmetric=false)
void vmult_add(Vector< number > &w, const Vector< number > &v) const
static ::ExceptionBase & ExcInternalError()