xref: /libCEED/tests/t305-basis.c (revision e6a04bf5cb06fd03ee882d1ea55149c09771081b)
1 /// @file
2 /// Test Simultaneous Diagonalization
3 /// \test Simultaneous Diagonalization
4 #include <ceed.h>
5 
6 int main(int argc, char **argv) {
7   Ceed ceed;
8   CeedScalar M[16] = {0.19996678, 0.0745459, -0.07448852, 0.0332866,
9                       0.0745459, 1., 0.16666509, -0.07448852,
10                       -0.07448852, 0.16666509, 1., 0.0745459,
11                       0.0332866, -0.07448852, 0.0745459, 0.19996678
12                      };
13   CeedScalar K[16] = {3.03344425, -3.41501767, 0.49824435, -0.11667092,
14                       -3.41501767, 5.83354662, -2.9167733, 0.49824435,
15                       0.49824435, -2.9167733, 5.83354662, -3.41501767,
16                       -0.11667092, 0.49824435, -3.41501767, 3.03344425
17                      };
18   CeedScalar x[16], lambda[4];
19 
20   CeedInit(argv[1], &ceed);
21 
22   CeedSimultaneousDiagonalization(ceed, K, M, x, lambda, 4);
23   fprintf(stdout, "x:\n");
24   for (int i=0; i<4; i++) {
25     for (int j=0; j<4; j++) {
26       if (x[j+4*i] <= 1E-14 && x[j+4*i] >= -1E-14) x[j+4*i] = 0;
27       fprintf(stdout, "%12.8f\t", x[j+4*i]);
28     }
29     fprintf(stdout, "\n");
30   }
31   fprintf(stdout, "lambda:\n");
32   for (int i=0; i<4; i++) {
33     if (lambda[i] <= 1E-14 && lambda[i] >= -1E-14) lambda[i] = 0;
34     fprintf(stdout, "%12.8f\n", lambda[i]);
35   }
36   CeedDestroy(&ceed);
37   return 0;
38 }
39