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41 
42 #include "Teuchos_SerialDenseMatrix.hpp"
43 #include "Teuchos_SerialDenseVector.hpp"
44 #include "Teuchos_SerialDenseHelpers.hpp"
45 #include "Teuchos_SerialDenseSolver.hpp"
46 #include "Teuchos_ScalarTraits.hpp"
47 #include "Teuchos_RCP.hpp"
48 #include "Teuchos_Version.hpp"
49 
50 using Teuchos::ScalarTraits;
51 using Teuchos::SerialDenseMatrix;
52 using Teuchos::SerialDenseVector;
53 
54 #define OTYPE int
55 #ifdef HAVE_TEUCHOS_COMPLEX
56 #define STYPE std::complex<double>
57 #else
58 #define STYPE double
59 #endif
60 
61 // SCALARMAX defines the maximum positive value (with a little leeway) generated for matrix and vector elements and scalars:
62 // random numbers in [-SCALARMAX, SCALARMAX] will be generated.
63 #ifdef HAVE_TEUCHOS_COMPLEX
64 #define SCALARMAX  STYPE(10,0)
65 #else
66 #define SCALARMAX  STYPE(10)
67 #endif
68 
69 template<typename TYPE>
70 int PrintTestResults(std::string, TYPE, TYPE, bool);
71 
72 int ReturnCodeCheck(std::string, int, int, bool);
73 
74 typedef SerialDenseVector<OTYPE, STYPE> DVector;
75 typedef SerialDenseMatrix<OTYPE, STYPE> DMatrix;
76 
77 // Returns ScalarTraits<TYPE>::random() (the input parameters are ignored)
78 template<typename TYPE>
79 TYPE GetRandom(TYPE, TYPE);
80 
81 // Returns a random integer between the two input parameters, inclusive
82 template<>
83 int GetRandom(int, int);
84 
85 // Returns a random double between the two input parameters, plus or minus a random number between 0 and 1
86 template<>
87 double GetRandom(double, double);
88 
89 template<typename T>
90 std::complex<T> GetRandom( std::complex<T>, std::complex<T> );
91 
92 // Generates random matrices and vectors using GetRandom()
93 Teuchos::RCP<DMatrix> GetRandomMatrix(int m, int n);
94 Teuchos::RCP<DVector> GetRandomVector(int n);
95 
96 // Compares the difference between two vectors using relative euclidean norms
97 // Returns 1 if the comparison failed, the relative difference is greater than the tolerance.
98 int CompareVectors(const SerialDenseVector<OTYPE,STYPE>& Vector1,
99                    const SerialDenseVector<OTYPE,STYPE>& Vector2,
100                    ScalarTraits<STYPE>::magnitudeType Tolerance,
101                    bool verbose);
102 
main(int argc,char * argv[])103 int main(int argc, char* argv[])
104 {
105   typedef ScalarTraits<STYPE>::magnitudeType MagnitudeType;
106 
107   int n=10, m=8;
108   (void) m; // forestall "unused variable" compiler warning
109   MagnitudeType tol = 1e-12*ScalarTraits<MagnitudeType>::one();
110 
111   bool verbose = 0;
112   if (argc>1) if (argv[1][0]=='-' && argv[1][1]=='v') verbose = true;
113 
114   if (verbose)
115     std::cout << Teuchos::Teuchos_Version() << std::endl << std::endl;
116 
117   int numberFailedTests = 0;
118   int returnCode = 0;
119   std::string testName = "", testType = "";
120 
121 #ifdef HAVE_TEUCHOS_COMPLEX
122   testType = "COMPLEX";
123 #else
124   testType = "REAL";
125 #endif
126 
127   if (verbose) std::cout<<std::endl<<"********** CHECKING TEUCHOS SERIAL DENSE SOLVER - " << testType << "-VALUED **********"<<std::endl<<std::endl;
128 
129   // Create dense matrix and vector.
130   Teuchos::RCP<DMatrix> A1 = GetRandomMatrix(n,n);
131   Teuchos::RCP<DVector> x1 = GetRandomVector(n);
132   DVector xhat(n), b(n), bt(n);
133 
134   // Compute the right-hand side vector using multiplication.
135   returnCode = b.multiply(Teuchos::NO_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, *x1, ScalarTraits<STYPE>::zero());
136   testName = "Generating right-hand side vector using A*x, where x is a random vector:";
137   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
138 
139   returnCode = bt.multiply(Teuchos::TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, *x1, ScalarTraits<STYPE>::zero());
140   testName = "Generating right-hand side vector using A^T*x, where x is a random vector:";
141   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
142 
143 #ifdef HAVE_TEUCHOS_COMPLEX
144   DVector bct(n);
145   returnCode = bct.multiply(Teuchos::CONJ_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, *x1, ScalarTraits<STYPE>::zero());
146   testName = "Generating right-hand side vector using A^H*x, where x is a random vector:";
147   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
148 #endif
149 
150   // Fill the solution vector with zeros.
151   xhat.putScalar( ScalarTraits<STYPE>::zero() );
152 
153   // Create a serial dense solver.
154   Teuchos::SerialDenseSolver<OTYPE, STYPE> solver1;
155 
156   // Pass in matrix and vectors
157   solver1.setMatrix( A1 );
158   solver1.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &b, false ) );
159 
160   // Test1:  Simple factor and solve
161   returnCode = solver1.factor();
162   testName = "Simple solve: factor() random A:";
163   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
164 
165   // Non-transpose solve
166   returnCode = solver1.solve();
167   testName = "Simple solve: solve() random A (NO_TRANS):";
168   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
169   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
170 
171   // Tranpose solve (can be done after factorization, since factorization doesn't depend on this)
172   xhat.putScalar( ScalarTraits<STYPE>::zero() );
173   solver1.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bt, false ) );
174   solver1.solveWithTransposeFlag( Teuchos::TRANS );
175   returnCode = solver1.solve();
176   testName = "Simple solve: solve() random A (TRANS):";
177   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
178   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
179 
180 #ifdef HAVE_TEUCHOS_COMPLEX
181   // Conjugate tranpose solve (can be done after factorization, since factorization doesn't depend on this)
182   xhat.putScalar( ScalarTraits<STYPE>::zero() );
183   solver1.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bct, false ) );
184   solver1.solveWithTransposeFlag( Teuchos::CONJ_TRANS );
185   returnCode = solver1.solve();
186   testName = "Simple solve: solve() random A (CONJ_TRANS):";
187   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
188   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
189 #endif
190 
191   // Test2: Invert the matrix, inverse should be in A.
192   returnCode = solver1.invert();
193   testName = "Simple solve: invert() random A:";
194   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
195 
196   // Compute the solution vector using multiplication and the inverse.
197   returnCode = xhat.multiply(Teuchos::NO_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, b, ScalarTraits<STYPE>::zero());
198   testName = "Computing solution using inverted random A (NO_TRANS):";
199   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
200   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
201 
202   returnCode = xhat.multiply(Teuchos::TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, bt, ScalarTraits<STYPE>::zero());
203   testName = "Computing solution using inverted random A (TRANS):";
204   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
205   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
206 
207 #ifdef HAVE_TEUCHOS_COMPLEX
208   returnCode = xhat.multiply(Teuchos::CONJ_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A1, bct, ScalarTraits<STYPE>::zero());
209   testName = "Computing solution using inverted random A (CONJ_TRANS):";
210   numberFailedTests += CompareVectors( *x1, xhat, tol, verbose );
211   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
212 #endif
213 
214   // Test3:  Solve with iterative refinement.
215 #ifdef HAVE_TEUCHOSNUMERICS_EIGEN
216   // Iterative refinement not implemented in Eigen
217 #else
218   // Create random linear system
219   Teuchos::RCP<DMatrix> A2 = GetRandomMatrix(n,n);
220   Teuchos::RCP<DVector> x2 = GetRandomVector(n);
221 
222   // Create LHS through multiplication with A2
223   xhat.putScalar( ScalarTraits<STYPE>::zero() );
224   b.multiply(Teuchos::NO_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A2, *x2, ScalarTraits<STYPE>::zero());
225   bt.multiply(Teuchos::TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A2, *x2, ScalarTraits<STYPE>::zero());
226 #ifdef HAVE_TEUCHOS_COMPLEX
227   bct.multiply(Teuchos::CONJ_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A2, *x2, ScalarTraits<STYPE>::zero());
228 #endif
229 
230   // Create a serial dense solver.
231   Teuchos::SerialDenseSolver<OTYPE, STYPE> solver2;
232   solver2.solveToRefinedSolution( true );
233 
234   // Pass in matrix and vectors
235   solver2.setMatrix( A2 );
236   solver2.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &b, false ) );
237 
238   // Factor and solve with iterative refinement.
239   returnCode = solver2.factor();
240   testName = "Solve with iterative refinement: factor() random A:";
241   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
242 
243   // Non-transpose solve
244   returnCode = solver2.solve();
245   testName = "Solve with iterative refinement: solve() random A (NO_TRANS):";
246   numberFailedTests += CompareVectors( *x2, xhat, tol, verbose );
247   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
248 
249   // Tranpose solve (can be done after factorization, since factorization doesn't depend on this)
250   xhat.putScalar( ScalarTraits<STYPE>::zero() );
251   solver2.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bt, false ) );
252   solver2.solveWithTransposeFlag( Teuchos::TRANS );
253   returnCode = solver2.solve();
254   testName = "Solve with iterative refinement: solve() random A (TRANS):";
255   numberFailedTests += CompareVectors( *x2, xhat, tol, verbose );
256   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
257 
258 #ifdef HAVE_TEUCHOS_COMPLEX
259   // Conjugate tranpose solve (can be done after factorization, since factorization doesn't depend on this)
260   xhat.putScalar( ScalarTraits<STYPE>::zero() );
261   solver2.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bct, false ) );
262   solver2.solveWithTransposeFlag( Teuchos::CONJ_TRANS );
263   returnCode = solver2.solve();
264   testName = "Solve with iterative refinement: solve() random A (CONJ_TRANS):";
265   numberFailedTests += CompareVectors( *x2, xhat, tol, verbose );
266   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
267 #endif
268 #endif
269 
270   // Test4:  Solve with matrix equilibration.
271 
272   // Create random linear system
273   Teuchos::RCP<DMatrix> A3 = GetRandomMatrix(n,n);
274   Teuchos::RCP<DVector> x3 = GetRandomVector(n);
275 
276   // Create LHS through multiplication with A3
277   xhat.putScalar( ScalarTraits<STYPE>::zero() );
278   b.multiply(Teuchos::NO_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A3, *x3, ScalarTraits<STYPE>::zero());
279   bt.multiply(Teuchos::TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A3, *x3, ScalarTraits<STYPE>::zero());
280 #ifdef HAVE_TEUCHOS_COMPLEX
281   bct.multiply(Teuchos::CONJ_TRANS, Teuchos::NO_TRANS, ScalarTraits<STYPE>::one() , *A3, *x3, ScalarTraits<STYPE>::zero());
282 #endif
283 
284   // Save backups for multiple solves.
285   Teuchos::RCP<DMatrix> A3bak = Teuchos::rcp( new DMatrix( Teuchos::Copy, *A3 ) );
286   Teuchos::RCP<DVector> b3bak = Teuchos::rcp( new DVector( Teuchos::Copy, b ) );
287 
288   // Create a serial dense solver.
289   Teuchos::SerialDenseSolver<OTYPE, STYPE> solver3;
290   solver3.factorWithEquilibration( true );
291 
292   // Pass in matrix and vectors
293   solver3.setMatrix( A3 );
294   solver3.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &b, false ) );
295 
296   // Factor and solve with matrix equilibration.
297   returnCode = solver3.factor();
298   testName = "Solve with matrix equilibration: factor() random A:";
299   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
300 
301   // Non-transpose solve
302   returnCode = solver3.solve();
303   testName = "Solve with matrix equilibration: solve() random A (NO_TRANS):";
304   numberFailedTests += CompareVectors( *x3, xhat, tol, verbose );
305   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
306 
307   // Tranpose solve (can be done after factorization, since factorization doesn't depend on this)
308   xhat.putScalar( ScalarTraits<STYPE>::zero() );
309   solver3.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bt, false ) );
310   solver3.solveWithTransposeFlag( Teuchos::TRANS );
311   returnCode = solver3.solve();
312   testName = "Solve with matrix equilibration: solve() random A (TRANS):";
313   numberFailedTests += CompareVectors( *x3, xhat, tol, verbose );
314   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
315 
316 #ifdef HAVE_TEUCHOS_COMPLEX
317   // Conjugate tranpose solve (can be done after factorization, since factorization doesn't depend on this)
318   xhat.putScalar( ScalarTraits<STYPE>::zero() );
319   solver3.setVectors( Teuchos::rcp( &xhat, false ), Teuchos::rcp( &bct, false ) );
320   solver3.solveWithTransposeFlag( Teuchos::CONJ_TRANS );
321   returnCode = solver3.solve();
322   testName = "Solve with matrix equilibration: solve() random A (CONJ_TRANS):";
323   numberFailedTests += CompareVectors( *x3, xhat, tol, verbose );
324   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
325 #endif
326 
327   // Factor and solve with matrix equilibration, only call solve not factor.
328   // Use copy of A3 and b, they were overwritten in last factor() call.
329   xhat.putScalar( ScalarTraits<STYPE>::zero() );
330   solver3.setMatrix( A3bak );
331   solver3.setVectors( Teuchos::rcp( &xhat, false ), b3bak );
332   solver3.solveWithTransposeFlag( Teuchos::NO_TRANS );
333   returnCode = solver3.solve();
334   testName = "Solve with matrix equilibration: solve() without factor() random A (NO_TRANS):";
335   numberFailedTests += CompareVectors( *x3, xhat, tol, verbose );
336   numberFailedTests += ReturnCodeCheck(testName, returnCode, 0, verbose);
337 
338   //
339   // If a test failed output the number of failed tests.
340   //
341   if(numberFailedTests > 0)
342   {
343             if (verbose) {
344                 std::cout << "Number of failed tests: " << numberFailedTests << std::endl;
345                 std::cout << "End Result: TEST FAILED" << std::endl;
346                 return -1;
347             }
348         }
349   if(numberFailedTests == 0)
350     std::cout << "End Result: TEST PASSED" << std::endl;
351 
352   return 0;
353 }
354 
355 template<typename TYPE>
PrintTestResults(std::string testName,TYPE calculatedResult,TYPE expectedResult,bool verbose)356 int PrintTestResults(std::string testName, TYPE calculatedResult, TYPE expectedResult, bool verbose)
357 {
358   int result;
359   if(calculatedResult == expectedResult)
360     {
361       if(verbose) std::cout << testName << " successful." << std::endl;
362       result = 0;
363     }
364   else
365     {
366       if(verbose) std::cout << testName << " unsuccessful." << std::endl;
367       result = 1;
368     }
369   return result;
370 }
371 
ReturnCodeCheck(std::string testName,int returnCode,int expectedResult,bool verbose)372 int ReturnCodeCheck(std::string testName, int returnCode, int expectedResult, bool verbose)
373 {
374   int result;
375   if(expectedResult == 0)
376     {
377       if(returnCode == 0)
378         {
379           if(verbose) std::cout << testName << " test successful." << std::endl;
380           result = 0;
381         }
382       else
383         {
384           if(verbose) std::cout << testName << " test unsuccessful. Return code was " << returnCode << "." << std::endl;
385           result = 1;
386         }
387     }
388   else
389     {
390       if(returnCode != 0)
391         {
392           if(verbose) std::cout << testName << " test successful -- failed as expected." << std::endl;
393           result = 0;
394         }
395       else
396         {
397           if(verbose) std::cout << testName << " test unsuccessful -- did not fail as expected. Return code was " << returnCode << "." << std::endl;
398           result = 1;
399         }
400     }
401   return result;
402 }
403 
404 template<typename TYPE>
GetRandom(TYPE Low,TYPE High)405 TYPE GetRandom(TYPE Low, TYPE High)
406 {
407   return ((TYPE)((double)((1.0 * ScalarTraits<int>::random()) / RAND_MAX) * (High - Low + 1)) + Low);
408 }
409 
410 template<typename T>
GetRandom(std::complex<T> Low,std::complex<T> High)411 std::complex<T> GetRandom( std::complex<T> Low, std::complex<T> High)
412 {
413   T lowMag = Low.real();
414   T highMag = High.real();
415   T real = (T)(((1.0 * ScalarTraits<int>::random()) / RAND_MAX) * (highMag - lowMag + ScalarTraits<T>::one())) + lowMag;
416   T imag = (T)(((1.0 * ScalarTraits<int>::random()) / RAND_MAX) * (highMag - lowMag + ScalarTraits<T>::one())) + lowMag;
417   return std::complex<T>( real, imag );
418 }
419 
420 template<>
GetRandom(int Low,int High)421 int GetRandom(int Low, int High)
422 {
423   return ((int)((double)((1.0 * ScalarTraits<int>::random()) / RAND_MAX) * (High - Low + 1)) + Low);
424 }
425 
426 template<>
GetRandom(double Low,double High)427 double GetRandom(double Low, double High)
428 {
429   return (((double)((1.0 * ScalarTraits<int>::random()) / RAND_MAX) * (High - Low + 1)) + Low + ScalarTraits<double>::random());
430 }
431 
GetRandomMatrix(int m,int n)432 Teuchos::RCP<DMatrix> GetRandomMatrix(int m, int n)
433 {
434   Teuchos::RCP<DMatrix> newmat = Teuchos::rcp( new DMatrix(m,n) );
435 
436   // Fill dense matrix with random entries.
437   for (int i=0; i<m; i++)
438     for (int j=0; j<n; j++)
439       (*newmat)(i,j) = GetRandom(-SCALARMAX, SCALARMAX);
440 
441   return newmat;
442 }
443 
GetRandomVector(int n)444 Teuchos::RCP<DVector> GetRandomVector(int n)
445 {
446   Teuchos::RCP<DVector> newvec = Teuchos::rcp( new DVector( n ) );
447 
448   // Fill dense vector with random entries.
449   for (int i=0; i<n; i++)
450     (*newvec)(i) = GetRandom(-SCALARMAX, SCALARMAX);
451 
452   return newvec;
453 }
454 
455 /*  Function:  CompareVectors
456     Purpose:   Compares the difference between two vectors using relative euclidean-norms, i.e. ||v_1-v_2||_2/||v_2||_2
457 */
CompareVectors(const SerialDenseVector<OTYPE,STYPE> & Vector1,const SerialDenseVector<OTYPE,STYPE> & Vector2,ScalarTraits<STYPE>::magnitudeType Tolerance,bool verbose)458 int CompareVectors(const SerialDenseVector<OTYPE,STYPE>& Vector1,
459                    const SerialDenseVector<OTYPE,STYPE>& Vector2,
460                    ScalarTraits<STYPE>::magnitudeType Tolerance,
461                    bool verbose)
462 {
463   typedef ScalarTraits<STYPE>::magnitudeType MagnitudeType;
464 
465   SerialDenseVector<OTYPE,STYPE> diff( Vector1 );
466   diff -= Vector2;
467 
468   MagnitudeType norm_diff = diff.normFrobenius();
469   MagnitudeType norm_v2 = Vector2.normFrobenius();
470   MagnitudeType temp = norm_diff;
471   if (norm_v2 != ScalarTraits<MagnitudeType>::zero())
472     temp /= norm_v2;
473 
474   if (temp > Tolerance)
475   {
476     if (verbose)
477      std::cout << "COMPARISON FAILED : ";
478     return 1;
479   }
480   else
481     return 0;
482 }
483