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Stokhos_HermiteBasisUnitTest.cpp
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43 
44 #include "Teuchos_UnitTestHarness.hpp"
45 #include "Teuchos_TestingHelpers.hpp"
46 #include "Teuchos_UnitTestRepository.hpp"
47 #include "Teuchos_GlobalMPISession.hpp"
48 
49 #include "Stokhos.hpp"
50 #include "Stokhos_UnitTestHelpers.hpp"
51 #ifdef HAVE_STOKHOS_FORUQTK
52 #include "Stokhos_gaussq.h"
53 #endif
54 
55 namespace HermiteBasisUnitTest {
56 
57  // Common setup for unit tests
58  template <typename OrdinalType, typename ValueType>
59  struct UnitTestSetup {
60  ValueType rtol, atol;
61  OrdinalType p;
62  Stokhos::HermiteBasis<OrdinalType,ValueType> basis;
63 
64  UnitTestSetup() : rtol(1e-12), atol(1e-7), p(10), basis(p) {}
65 
66  };
67 
68  UnitTestSetup<int,double> setup;
69 
70  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Order ) {
71  int order = setup.basis.order();
72  TEUCHOS_TEST_EQUALITY(order, setup.p, out, success);
73  }
74 
75  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Size ) {
76  int size = setup.basis.size();
77  TEUCHOS_TEST_EQUALITY(size, setup.p+1, out, success);
78  }
79 
80  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Norm ) {
81  const Teuchos::Array<double>& n1 = setup.basis.norm_squared();
82  Teuchos::Array<double> n2(setup.p+1);
83  n2[0] = 1.0;
84  for (int i=1; i<=setup.p; i++)
85  n2[i] = i*n2[i-1];
86  success = Stokhos::compareArrays(n1, "n1", n2, "n2", setup.rtol, setup.atol,
87  out);
88  }
89 
90  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Norm2 ) {
91  Teuchos::Array<double> n1(setup.p+1);
92  Teuchos::Array<double> n2(setup.p+1);
93  n1[0] = setup.basis.norm_squared(0);
94  n2[0] = 1.0;
95  for (int i=1; i<=setup.p; i++) {
96  n1[i] = setup.basis.norm_squared(i);
97  n2[i] = i*n2[i-1];
98  }
99  success = Stokhos::compareArrays(n1, "n1", n2, "n2", setup.rtol, setup.atol,
100  out);
101  }
102 
103  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, QuadNorm ) {
104  const Teuchos::Array<double>& n1 = setup.basis.norm_squared();
105  Teuchos::Array<double> n2(setup.p+1);
106  Teuchos::Array<double> x, w;
107  Teuchos::Array< Teuchos::Array<double> > v;
108  setup.basis.getQuadPoints(2*setup.p, x, w, v);
109  int nqp = w.size();
110  for (int i=0; i<=setup.p; i++) {
111  n2[i] = 0;
112  for (int j=0; j<nqp; j++)
113  n2[i] += w[j]*v[j][i]*v[j][i];
114  }
115  success = Stokhos::compareArrays(n1, "n1", n2, "n2", setup.rtol, setup.atol,
116  out);
117  }
118 
119  // Tests basis is orthogonal
120  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, QuadOrthog ) {
121  const Teuchos::Array<double>& norms = setup.basis.norm_squared();
122  Teuchos::Array<double> x, w;
123  Teuchos::Array< Teuchos::Array<double> > v;
124  setup.basis.getQuadPoints(2*setup.p, x, w, v);
125  int nqp = w.size();
126  Teuchos::SerialDenseMatrix<int,double> mat(setup.p+1, setup.p+1);
127  for (int i=0; i<=setup.p; i++) {
128  for (int j=0; j<=setup.p; j++) {
129  for (int k=0; k<nqp; k++)
130  mat(i,j) += w[k]*v[k][i]*v[k][j];
131  mat(i,j) /= std::sqrt(norms[i]*norms[j]);
132  }
133  mat(i,i) -= 1.0;
134  }
135  success = mat.normInf() < setup.atol;
136  if (!success) {
137  out << "\n Error, mat.normInf() < atol = " << mat.normInf()
138  << " < " << setup.atol << ": failed!\n";
139  out << "mat = " << mat << std::endl;
140  }
141  }
142 
143  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, TripleProduct ) {
144  Teuchos::RCP< Stokhos::Dense3Tensor<int, double> > Cijk =
145  setup.basis.computeTripleProductTensor();
146 
147  Teuchos::Array<double> x, w;
148  Teuchos::Array< Teuchos::Array<double> > v;
149  setup.basis.getQuadPoints(3*setup.p, x, w, v);
150 
151  success = true;
152  for (int i=0; i<=setup.p; i++) {
153  for (int j=0; j<=setup.p; j++) {
154  for (int k=0; k<=setup.p; k++) {
155  double c = 0.0;
156  int nqp = w.size();
157  for (int qp=0; qp<nqp; qp++)
158  c += w[qp]*v[qp][i]*v[qp][j]*v[qp][k];
159  std::stringstream ss;
160  ss << "Cijk(" << i << "," << j << "," << k << ")";
161  success = success &&
162  Stokhos::compareValues((*Cijk)(i,j,k), ss.str(), c, "c",
163  setup.rtol, setup.atol, out);
164  }
165  }
166  }
167  }
168 
169  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, DerivDoubleProduct ) {
170  Teuchos::RCP< Teuchos::SerialDenseMatrix<int, double> > Bij =
171  setup.basis.computeDerivDoubleProductTensor();
172 
173  Teuchos::Array<double> x, w;
174  Teuchos::Array< Teuchos::Array<double> > v, val, deriv;
175  setup.basis.getQuadPoints(2*setup.p, x, w, v);
176  int nqp = w.size();
177  val.resize(nqp);
178  deriv.resize(nqp);
179  for (int i=0; i<nqp; i++) {
180  val[i].resize(setup.p+1);
181  deriv[i].resize(setup.p+1);
182  setup.basis.evaluateBasesAndDerivatives(x[i], val[i], deriv[i]);
183  }
184 
185  success = true;
186  for (int i=0; i<=setup.p; i++) {
187  for (int j=0; j<=setup.p; j++) {
188  double b = 0.0;
189  for (int qp=0; qp<nqp; qp++)
190  b += w[qp]*deriv[qp][i]*val[qp][j];
191  std::stringstream ss;
192  ss << "Bij(" << i << "," << j << ")";
193  success = success &&
194  Stokhos::compareValues((*Bij)(i,j), ss.str(), b, "b",
195  setup.rtol, setup.atol, out);
196  }
197  }
198  }
199 
200  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, DerivDoubleProduct2 ) {
201  Teuchos::RCP< Teuchos::SerialDenseMatrix<int, double> > Bij =
202  setup.basis.computeDerivDoubleProductTensor();
203  const Teuchos::Array<double>& n = setup.basis.norm_squared();
204 
205  success = true;
206  for (int i=0; i<=setup.p; i++) {
207  for (int j=0; j<=setup.p; j++) {
208  double b = 0.0;
209  if (j == i-1)
210  b = i*n[j];
211  std::stringstream ss;
212  ss << "Bij(" << i << "," << j << ")";
213  success = success &&
214  Stokhos::compareValues((*Bij)(i,j), ss.str(), b, "b",
215  setup.rtol, setup.atol, out);
216  }
217  }
218  }
219 
220  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, EvaluateBases ) {
221  double x = 0.1234;
222  Teuchos::Array<double> v1(setup.p+1), v2(setup.p+1);
223  setup.basis.evaluateBases(x, v1);
224 
225  // evaluate bases using formula
226  // He_0(x) = 1
227  // He_1(x) = x
228  // He_i(x) = x*He_{i-1}(x) - (i-1)*He_{i-2}(x), i=2,3,...
229  v2[0] = 1.0;
230  if (setup.p >= 1)
231  v2[1] = x;
232  for (int i=2; i<=setup.p; i++)
233  v2[i] = x*v2[i-1] - (i-1.0)*v2[i-2];
234  success = Stokhos::compareArrays(v1, "v1", v2, "v2", setup.rtol, setup.atol,
235  out);
236  }
237 
238  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, EvaluateBasesAndDerivatives ) {
239  double x = 0.1234;
240  Teuchos::Array<double> val1(setup.p+1), deriv1(setup.p+1),
241  val2(setup.p+1), deriv2(setup.p+1);
242  setup.basis.evaluateBasesAndDerivatives(x, val1, deriv1);
243 
244  // evaluate bases and derivatives using formula:
245  // He_0(x) = 1
246  // He_1(x) = x
247  // He_i(x) = x*He_{i-1}(x) - (i-1)*He_{i-2}(x), i=2,3,...
248  val2[0] = 1.0;
249  if (setup.p >= 1)
250  val2[1] = x;
251  for (int i=2; i<=setup.p; i++)
252  val2[i] = x*val2[i-1] - (i-1.0)*val2[i-2];
253 
254  deriv2[0] = 0.0;
255  if (setup.p >= 1)
256  deriv2[1] = 1.0;
257  for (int i=2; i<=setup.p; i++)
258  deriv2[i] = i*val2[i-1];
259  success = Stokhos::compareArrays(val1, "val1", val2, "val2",
260  setup.rtol, setup.atol, out);
261  success = success &&
262  Stokhos::compareArrays(deriv1, "deriv1", deriv2, "deriv2",
263  setup.rtol, setup.atol, out);
264 
265 
266  }
267 
268  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Evaluate ) {
269  double x = 0.1234;
270  Teuchos::Array<double> v1(setup.p+1), v2(setup.p+1);
271  for (int i=0; i<=setup.p; i++)
272  v1[i] = setup.basis.evaluate(x, i);
273 
274  // evaluate bases using formula
275  // He_0(x) = 1
276  // He_1(x) = x
277  // He_i(x) = x*He_{i-1}(x) - (i-1)*He_{i-2}(x), i=2,3,...
278  v2[0] = 1.0;
279  if (setup.p >= 1)
280  v2[1] = x;
281  for (int i=2; i<=setup.p; i++)
282  v2[i] = x*v2[i-1] - (i-1.0)*v2[i-2];
283  success = Stokhos::compareArrays(v1, "v1", v2, "v2", setup.rtol, setup.atol,
284  out);
285  }
286 
287  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, Recurrence ) {
288  Teuchos::Array<double> a1(setup.p+1), b1(setup.p+1), c1(setup.p+1),
289  d1(setup.p+1);
290  Teuchos::Array<double> a2(setup.p+1), b2(setup.p+1), c2(setup.p+1),
291  d2(setup.p+1);
292  setup.basis.getRecurrenceCoefficients(a1, b1, c1, d1);
293 
294  // compute coefficients using formula
295  a2[0] = 0.0; b2[0] = 1.0; c2[0] = 1.0; d2[0] = 1.0;
296  for (int i=1; i<=setup.p; i++) {
297  a2[i] = 0.0;
298  b2[i] = i;
299  c2[i] = 1.0;
300  d2[i] = 1.0;
301  }
302  success = true;
303  success = success &&
304  Stokhos::compareArrays(a1, "a1", a2, "a2", setup.rtol, setup.atol, out);
305  success = success &&
306  Stokhos::compareArrays(b1, "b1", b2, "b2", setup.rtol, setup.atol, out);
307  success = success &&
308  Stokhos::compareArrays(c1, "c1", c2, "c2", setup.rtol, setup.atol, out);
309  success = success &&
310  Stokhos::compareArrays(d1, "d1", d2, "d2", setup.rtol, setup.atol, out);
311  }
312 
313  // Tests alpha coefficients satisfy
314  // alpha_k = delta_k * (t*psi_k,psi_k)/(psi_k,psi_k)
315  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, RecurrenceAlpha ) {
316  Teuchos::Array<double> a1(setup.p+1), b1(setup.p+1), c1(setup.p+1),
317  d1(setup.p+1);
318  setup.basis.getRecurrenceCoefficients(a1, b1, c1, d1);
319 
320  Teuchos::Array<double> a2(setup.p+1);
321  const Teuchos::Array<double>& n1 = setup.basis.norm_squared();
322  Teuchos::Array<double> x, w;
323  Teuchos::Array< Teuchos::Array<double> > v;
324  setup.basis.getQuadPoints(2*setup.p, x, w, v);
325  int nqp = w.size();
326  for (int i=0; i<=setup.p; i++) {
327  a2[i] = 0;
328  for (int j=0; j<nqp; j++)
329  a2[i] += w[j]*x[j]*v[j][i]*v[j][i];
330  a2[i] = a2[i]*c1[i]/n1[i];
331  }
332  success = Stokhos::compareArrays(a1, "a1", a2, "a2", setup.rtol, setup.atol,
333  out);
334  }
335 
336  // Tests beta coefficients satisfy
337  // beta_k =
338  // gamma_k * delta_k/delta_{k-1} * (psi_k,psi_k)/(psi_{k-1},psi_{k-1})
339  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, RecurrenceBeta ) {
340  Teuchos::Array<double> a1(setup.p+1), b1(setup.p+1), c1(setup.p+1),
341  d1(setup.p+1);
342  setup.basis.getRecurrenceCoefficients(a1, b1, c1, d1);
343 
344  Teuchos::Array<double> b2(setup.p+1);
345  const Teuchos::Array<double>& n1 = setup.basis.norm_squared();
346  b2[0] = b1[0];
347  for (int i=1; i<=setup.p; i++) {
348  b2[i] = d1[i]*(c1[i]/c1[i-1])*(n1[i]/n1[i-1]);
349  }
350  success = Stokhos::compareArrays(b1, "b1", b2, "b2", setup.rtol, setup.atol,
351  out);
352  }
353 
354 #ifdef HAVE_STOKHOS_DAKOTA
355  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, QuadPointsDakota ) {
356  int n = static_cast<int>(std::ceil((setup.p+1)/2.0));
357  Teuchos::Array<double> x1, w1;
358  Teuchos::Array< Teuchos::Array<double> > v1;
359  setup.basis.getQuadPoints(setup.p, x1, w1, v1);
360 
361  Teuchos::Array<double> x2(n), w2(n);
362  Teuchos::Array< Teuchos::Array<double> > v2(n);
363  webbur::hermite_compute(n, &x2[0], &w2[0]);
364 
365  for (int i=0; i<n; i++) {
366  w2[i] *= 0.5/std::sqrt(std::atan(1.0)); // 1/sqrt(pi)
367  x2[i] *= std::sqrt(2.0);
368  v2[i].resize(setup.p+1);
369  setup.basis.evaluateBases(x2[i], v2[i]);
370  }
371  success = true;
372  success = success &&
373  Stokhos::compareArrays(x1, "x1", x2, "x2", setup.rtol, setup.atol, out);
374  success = success &&
375  Stokhos::compareArrays(w1, "w1", w2, "w2", setup.rtol, setup.atol, out);
376  for (int i=0; i<n; i++) {
377  std::stringstream ss1, ss2;
378  ss1 << "v1[" << i << "]";
379  ss2 << "v2[" << i << "]";
380  success = success &&
381  Stokhos::compareArrays(v1[i], ss1.str(), v2[i], ss2.str(),
382  setup.rtol, setup.atol, out);
383  }
384  }
385 #endif
386 
387 #ifdef HAVE_STOKHOS_FORUQTK
388  TEUCHOS_UNIT_TEST( Stokhos_HermiteBasis, QuadPointsForUQTK ) {
389  int n = static_cast<int>(std::ceil((setup.p+1)/2.0));
390  Teuchos::Array<double> x1, w1;
391  Teuchos::Array< Teuchos::Array<double> > v1;
392  setup.basis.getQuadPoints(setup.p, x1, w1, v1);
393 
394  Teuchos::Array<double> x2(n), w2(n);
395  Teuchos::Array< Teuchos::Array<double> > v2(n);
396  int kind = 4;
397  int kpts = 0;
398  double endpts[2] = {0.0, 0.0};
399  Teuchos::Array<double> b(n);
400  double alpha = 0.0;
401  double beta = 0.0;
402  GAUSSQ_F77(&kind, &n, &alpha, &beta, &kpts, endpts, &b[0], &x2[0], &w2[0]);
403 
404  for (int i=0; i<n; i++) {
405  w2[i] *= 0.5/std::sqrt(std::atan(1.0)); // 1/sqrt(pi)
406  x2[i] *= std::sqrt(2.0);
407  v2[i].resize(setup.p+1);
408  setup.basis.evaluateBases(x2[i], v2[i]);
409  }
410  success = true;
411  success = success &&
412  Stokhos::compareArrays(x1, "x1", x2, "x2", setup.rtol, setup.atol, out);
413  success = success &&
414  Stokhos::compareArrays(w1, "w1", w2, "w2", setup.rtol, setup.atol, out);
415  for (int i=0; i<n; i++) {
416  std::stringstream ss1, ss2;
417  ss1 << "v1[" << i << "]";
418  ss2 << "v2[" << i << "]";
419  success = success &&
420  Stokhos::compareArrays(v1[i], ss1.str(), v2[i], ss2.str(),
421  setup.rtol, setup.atol, out);
422  }
423  }
424 #endif
425 
426 }
427 
428 int main( int argc, char* argv[] ) {
429  Teuchos::GlobalMPISession mpiSession(&argc, &argv);
430  return Teuchos::UnitTestRepository::runUnitTestsFromMain(argc, argv);
431 }
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