xref: /libCEED/tests/t532-operator.h (revision 6eb06d7cb0f5787c494a4969c0aa6769f3bcfbd0)
1 // Copyright (c) 2017-2025, 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 #include <ceed/types.h>
9 
10 CEED_QFUNCTION(setup_mass)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
11   const CeedScalar *J = in[0], *weight = in[1];
12   CeedScalar       *rho = out[0];
13   for (CeedInt i = 0; i < Q; i++) {
14     rho[i] = weight[i] * (J[i + Q * 0] * J[i + Q * 3] - J[i + Q * 1] * J[i + Q * 2]);
15   }
16   return 0;
17 }
18 
19 CEED_QFUNCTION(setup_diff)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
20   // At every quadrature point, compute qw/det(J).adj(J).adj(J)^T and store
21   // the symmetric part of the result.
22 
23   // in[0] is Jacobians with shape [2, nc=2, Q]
24   // in[1] is quadrature weights, size (Q)
25   const CeedScalar *J = in[0], *qw = in[1];
26 
27   // out[0] is qdata, size (Q)
28   CeedScalar *qd = out[0];
29 
30   // Quadrature point loop
31   for (CeedInt i = 0; i < Q; i++) {
32     // J: 0 2   qd: 0 2   adj(J):  J22 -J12
33     //    1 3       2 1           -J21  J11
34     const CeedScalar J11 = J[i + Q * 0];
35     const CeedScalar J21 = J[i + Q * 1];
36     const CeedScalar J12 = J[i + Q * 2];
37     const CeedScalar J22 = J[i + Q * 3];
38     const CeedScalar w   = qw[i] / (J11 * J22 - J21 * J12);
39     qd[i + Q * 0]        = w * (J12 * J12 + J22 * J22);
40     qd[i + Q * 1]        = w * (J11 * J11 + J21 * J21);
41     qd[i + Q * 2]        = -w * (J11 * J12 + J21 * J22);
42   }
43 
44   return 0;
45 }
46 
47 CEED_QFUNCTION(apply)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
48   // in[0] is gradient u, shape [2, nc=1, Q]
49   // in[1] is mass quadrature data, size (Q)
50   // in[2] is Poisson quadrature data, size (3*Q)
51   // in[3] is u, size (Q)
52   const CeedScalar *du = in[0], *qd_mass = in[1], *qd_diff = in[2], *u = in[3];
53 
54   // out[0] is output to multiply against v, size (Q)
55   // out[1] is output to multiply against gradient v, shape [2, nc=1, Q]
56   CeedScalar *v = out[0], *dv = out[1];
57 
58   // Quadrature point loop
59   for (CeedInt i = 0; i < Q; i++) {
60     // Mass
61     v[i] = qd_mass[i] * u[i];
62     // Diff
63     const CeedScalar du0 = du[i + Q * 0];
64     const CeedScalar du1 = du[i + Q * 1];
65     dv[i + Q * 0]        = qd_diff[i + Q * 0] * du0 + qd_diff[i + Q * 2] * du1;
66     dv[i + Q * 1]        = qd_diff[i + Q * 2] * du0 + qd_diff[i + Q * 1] * du1;
67   }
68 
69   return 0;
70 }
71 
72 CEED_QFUNCTION(apply_lin)(void *ctx, const CeedInt Q, const CeedScalar *const *in, CeedScalar *const *out) {
73   // in[0] is gradient u, shape [2, nc=1, Q]
74   // in[1] is assembled quadrature data, size (9*Q)
75   // in[2] is u, size (Q)
76   const CeedScalar *du = in[0], *qd = in[1], *u = in[2];
77 
78   // out[0] is output to multiply against v, size (Q)
79   // out[1] is output to multiply against gradient v, shape [2, nc=1, Q]
80   CeedScalar *v = out[0], *dv = out[1];
81 
82   // Quadrature point loop
83   for (CeedInt i = 0; i < Q; i++) {
84     const CeedScalar du0 = du[i + Q * 0];
85     const CeedScalar du1 = du[i + Q * 1];
86     v[i + Q * 0]         = qd[i + Q * 0] * du0 + qd[i + Q * 3] * du1 + qd[i + Q * 6] * u[i];
87     dv[i + Q * 0]        = qd[i + Q * 1] * du0 + qd[i + Q * 4] * du1 + qd[i + Q * 7] * u[i];
88     dv[i + Q * 1]        = qd[i + Q * 2] * du0 + qd[i + Q * 5] * du1 + qd[i + Q * 8] * u[i];
89   }
90 
91   return 0;
92 }
93