xref: /libCEED/examples/petsc/qfunctions/bps/bp4.h (revision 74653b0dfd9ea5453a7e0d931542e0b08b318f8b)
1 // Copyright (c) 2017, Lawrence Livermore National Security, LLC. Produced at
2 // the Lawrence Livermore National Laboratory. LLNL-CODE-734707. All Rights
3 // reserved. See files LICENSE and NOTICE for details.
4 //
5 // This file is part of CEED, a collection of benchmarks, miniapps, software
6 // libraries and APIs for efficient high-order finite element and spectral
7 // element discretizations for exascale applications. For more information and
8 // source code availability see http://github.com/ceed.
9 //
10 // The CEED research is supported by the Exascale Computing Project 17-SC-20-SC,
11 // a collaborative effort of two U.S. Department of Energy organizations (Office
12 // of Science and the National Nuclear Security Administration) responsible for
13 // the planning and preparation of a capable exascale ecosystem, including
14 // software, applications, hardware, advanced system engineering and early
15 // testbed platforms, in support of the nation's exascale computing imperative.
16 
17 /// @file
18 /// libCEED QFunctions for diffusion operator example using PETSc
19 
20 #ifndef bp4_h
21 #define bp4_h
22 
23 #ifndef __CUDACC__
24 #  include <math.h>
25 #endif
26 
27 // -----------------------------------------------------------------------------
28 // This QFunction sets up the rhs and true solution for the problem
29 // -----------------------------------------------------------------------------
30 CEED_QFUNCTION(SetupDiffRhs3)(void *ctx, CeedInt Q,
31                               const CeedScalar *const *in,
32                               CeedScalar *const *out) {
33 #ifndef M_PI
34 #  define M_PI    3.14159265358979323846
35 #endif
36   const CeedScalar *x = in[0], *w = in[1];
37   CeedScalar *true_soln = out[0], *rhs = out[1];
38 
39   // Quadrature Point Loop
40   CeedPragmaSIMD
41   for (CeedInt i=0; i<Q; i++) {
42     const CeedScalar c[3] = { 0, 1., 2. };
43     const CeedScalar k[3] = { 1., 2., 3. };
44 
45     // Component 1
46     true_soln[i+0*Q] = sin(M_PI*(c[0] + k[0]*x[i+Q*0])) *
47                        sin(M_PI*(c[1] + k[1]*x[i+Q*1])) *
48                        sin(M_PI*(c[2] + k[2]*x[i+Q*2]));
49     // Component 2
50     true_soln[i+1*Q] = 2 * true_soln[i+0*Q];
51     // Component 3
52     true_soln[i+2*Q] = 3 * true_soln[i+0*Q];
53 
54     // Component 1
55     rhs[i+0*Q] = w[i+Q*6] * M_PI*M_PI * (k[0]*k[0] + k[1]*k[1] + k[2]*k[2]) *
56                  true_soln[i+0*Q];
57     // Component 2
58     rhs[i+1*Q] = 2 * rhs[i+0*Q];
59     // Component 3
60     rhs[i+2*Q] = 3 * rhs[i+0*Q];
61   } // End of Quadrature Point Loop
62 
63   return 0;
64 }
65 
66 // -----------------------------------------------------------------------------
67 // This QFunction applies the diffusion operator for a vector field of 3 components.
68 //
69 // Inputs:
70 //   ug     - Input vector Jacobian at quadrature points
71 //   q_data  - Geometric factors
72 //
73 // Output:
74 //   vJ     - Output vector (test functions) Jacobian at quadrature points
75 //
76 // -----------------------------------------------------------------------------
77 CEED_QFUNCTION(Diff3)(void *ctx, CeedInt Q,
78                      const CeedScalar *const *in, CeedScalar *const *out) {
79   const CeedScalar *ug = in[0], *qd = in[1];
80   CeedScalar *vg = out[0];
81 
82   // Quadrature Point Loop
83   CeedPragmaSIMD
84   for (CeedInt i=0; i<Q; i++) {
85     // Read spatial derivatives of u components
86     const CeedScalar uJ[3][3]         = {{ug[i+(0+0*3)*Q],
87                                           ug[i+(0+1*3)*Q],
88                                           ug[i+(0+2*3)*Q]},
89                                          {ug[i+(1+0*3)*Q],
90                                           ug[i+(1+1*3)*Q],
91                                           ug[i+(1+2*3)*Q]},
92                                          {ug[i+(2+0*3)*Q],
93                                           ug[i+(2+1*3)*Q],
94                                           ug[i+(2+2*3)*Q]}
95                                         };
96     // Read q_data (dXdxdXdx_T symmetric matrix)
97     const CeedScalar dXdxdXdx_T[3][3] = {{qd[i+0*Q],
98                                           qd[i+1*Q],
99                                           qd[i+2*Q]},
100                                          {qd[i+1*Q],
101                                           qd[i+3*Q],
102                                           qd[i+4*Q]},
103                                          {qd[i+2*Q],
104                                           qd[i+4*Q],
105                                           qd[i+5*Q]}
106                                         };
107 
108     for (int k=0; k<3; k++) // k = component
109       for (int j=0; j<3; j++) // j = direction of vg
110         vg[i+(k+j*3)*Q] = (uJ[k][0] * dXdxdXdx_T[0][j] +
111                            uJ[k][1] * dXdxdXdx_T[1][j] +
112                            uJ[k][2] * dXdxdXdx_T[2][j]);
113   } // End of Quadrature Point Loop
114 
115   return 0;
116 }
117 // -----------------------------------------------------------------------------
118 
119 #endif // bp4_h
120