1 // Copyright (c) 2017-2026, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
3 //
4 // SPDX-License-Identifier: BSD-2-Clause
5 //
6 // This file is part of CEED: http://github.com/ceed
7
8 /// @file
9 /// libCEED QFunctions for diffusion operator example using PETSc
10
11 #include <ceed/types.h>
12 #ifndef CEED_RUNNING_JIT_PASS
13 #include <math.h>
14 #endif
15
16 // -----------------------------------------------------------------------------
17 // This QFunction sets up the rhs and true solution for the problem
18 // -----------------------------------------------------------------------------
SetupMassDiffRhs(void * ctx,const CeedInt Q,const CeedScalar * const * in,CeedScalar * const * out)19 CEED_QFUNCTION(SetupMassDiffRhs)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
20 #ifndef M_PI
21 #define M_PI 3.14159265358979323846
22 #endif
23 const CeedScalar *x = in[0], *w = in[1];
24 CeedScalar *true_soln = out[0], *rhs = out[1];
25
26 // Quadrature Point Loop
27 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
28 const CeedScalar c[3] = {0, 1., 2.};
29 const CeedScalar k[3] = {1., 2., 3.};
30
31 true_soln[i] = sin(M_PI * (c[0] + k[0] * x[i + Q * 0])) * sin(M_PI * (c[1] + k[1] * x[i + Q * 1])) * sin(M_PI * (c[2] + k[2] * x[i + Q * 2]));
32
33 rhs[i] = w[i + Q * 0] * (M_PI * M_PI * (k[0] * k[0] + k[1] * k[1] + k[2] * k[2]) + 1.0) * true_soln[i];
34 } // End of Quadrature Point Loop
35 return 0;
36 }
37
38 // -----------------------------------------------------------------------------
39 // This QFunction applies the mass + diffusion operator for a scalar field.
40 //
41 // Inputs:
42 // u - Input vector at quadrature points
43 // ug - Input vector gradient at quadrature points
44 // q_data - Geometric factors
45 //
46 // Output:
47 // v - Output vector (test functions) at quadrature points
48 // vg - Output vector (test functions) gradient at quadrature points
49 // -----------------------------------------------------------------------------
MassDiff(void * ctx,CeedInt Q,const CeedScalar * const * in,CeedScalar * const * out)50 CEED_QFUNCTION(MassDiff)(void *ctx, CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
51 const CeedScalar *u = in[0], *ug = in[1], *q_data = in[2];
52 CeedScalar *v = out[0], *vg = out[1];
53
54 // Quadrature Point Loop
55 CeedPragmaSIMD for (CeedInt i = 0; i < Q; i++) {
56 // Read spatial derivatives of u
57 const CeedScalar du[3] = {ug[i + Q * 0], ug[i + Q * 1], ug[i + Q * 2]};
58 // Read q_data (dXdxdXdx_T symmetric matrix)
59 const CeedScalar dXdxdXdx_T[3][3] = {
60 {q_data[i + 1 * Q], q_data[i + 2 * Q], q_data[i + 3 * Q]},
61 {q_data[i + 2 * Q], q_data[i + 4 * Q], q_data[i + 5 * Q]},
62 {q_data[i + 3 * Q], q_data[i + 5 * Q], q_data[i + 6 * Q]}
63 };
64
65 // Mass
66 v[i] = q_data[i + 0 * Q] * u[i];
67 // Diff
68 for (int j = 0; j < 3; j++) { // j = direction of vg
69 vg[i + j * Q] = (du[0] * dXdxdXdx_T[0][j] + du[1] * dXdxdXdx_T[1][j] + du[2] * dXdxdXdx_T[2][j]);
70 }
71 } // End of Quadrature Point Loop
72 return 0;
73 }
74 // -----------------------------------------------------------------------------
75