xref: /libCEED/tests/t321-basis.c (revision daadeac6547c0bce0e170b8a41c931051f52e9a3)
1 /// @file
2 /// Test interpolation with a 2D Simplex non-tensor H1 basis
3 /// \test Test interpolaton with a 2D Simplex non-tensor H1 basis
4 #include <ceed.h>
5 #include <math.h>
6 
7 #include "t320-basis.h"
8 
9 // polynomial eval helper
10 static CeedScalar feval(CeedScalar x1, CeedScalar x2) { return x1 * x1 + x2 * x2 + x1 * x2 + 1; }
11 
12 // main test
13 int main(int argc, char **argv) {
14   Ceed              ceed;
15   CeedVector        In, Out;
16   const CeedInt     P = 6, Q = 4, dim = 2;
17   CeedBasis         b;
18   CeedScalar        q_ref[dim * Q], q_weight[Q];
19   CeedScalar        interp[P * Q], grad[dim * P * Q];
20   CeedScalar        xq[] = {0.2, 0.6, 1. / 3., 0.2, 0.2, 0.2, 1. / 3., 0.6};
21   CeedScalar        xr[] = {0., 0.5, 1., 0., 0.5, 0., 0., 0., 0., 0.5, 0.5, 1.};
22   const CeedScalar *out;
23   CeedScalar        in[P], value;
24 
25   buildmats(q_ref, q_weight, interp, grad);
26 
27   CeedInit(argv[1], &ceed);
28 
29   CeedBasisCreateH1(ceed, CEED_TOPOLOGY_TRIANGLE, 1, P, Q, interp, grad, q_ref, q_weight, &b);
30 
31   // Interpolate function to quadrature points
32   for (int i = 0; i < P; i++) in[i] = feval(xr[0 * P + i], xr[1 * P + i]);
33 
34   CeedVectorCreate(ceed, P, &In);
35   CeedVectorSetArray(In, CEED_MEM_HOST, CEED_USE_POINTER, in);
36   CeedVectorCreate(ceed, Q, &Out);
37   CeedVectorSetValue(Out, 0);
38 
39   CeedBasisApply(b, 1, CEED_NOTRANSPOSE, CEED_EVAL_INTERP, In, Out);
40 
41   // Check values at quadrature points
42   CeedVectorGetArrayRead(Out, CEED_MEM_HOST, &out);
43   for (int i = 0; i < Q; i++) {
44     value = feval(xq[0 * Q + i], xq[1 * Q + i]);
45     if (fabs(out[i] - value) > 100. * CEED_EPSILON) printf("[%" CeedInt_FMT "] %f != %f\n", i, out[i], value);
46   }
47   CeedVectorRestoreArrayRead(Out, &out);
48 
49   CeedVectorDestroy(&In);
50   CeedVectorDestroy(&Out);
51   CeedBasisDestroy(&b);
52   CeedDestroy(&ceed);
53   return 0;
54 }
55