1 // Copyright (c) 2017-2022, 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 CEED_QFUNCTION(setup)(void *ctx, const CeedInt Q, 9 const CeedScalar *const *in, 10 CeedScalar *const *out) { 11 // At every quadrature point, compute qw/det(J).adj(J).adj(J)^T and store 12 // the symmetric part of the result. 13 14 // in[0] is Jacobians with shape [2, nc=2, Q] 15 // in[1] is quadrature weights, size (Q) 16 const CeedScalar *J = in[0], *qw = in[1]; 17 18 // out[0] is qdata, size (Q) 19 CeedScalar *qd = out[0]; 20 21 // Quadrature point loop 22 for (CeedInt i=0; i<Q; i++) { 23 // J: 0 2 qd: 0 2 adj(J): J22 -J12 24 // 1 3 2 1 -J21 J11 25 const CeedScalar J11 = J[i+Q*0]; 26 const CeedScalar J21 = J[i+Q*1]; 27 const CeedScalar J12 = J[i+Q*2]; 28 const CeedScalar J22 = J[i+Q*3]; 29 const CeedScalar w = qw[i] / (J11*J22 - J21*J12); 30 qd[i+Q*0] = w * (J12*J12 + J22*J22); 31 qd[i+Q*2] = w * (J11*J11 + J21*J21); 32 qd[i+Q*1] = - w * (J11*J12 + J21*J22); 33 } 34 35 return 0; 36 } 37 38 CEED_QFUNCTION(diff)(void *ctx, const CeedInt Q, const CeedScalar *const *in, 39 CeedScalar *const *out) { 40 // in[0] is gradient u, shape [2, nc=1, Q] 41 // in[1] is quadrature data, size (3*Q) 42 const CeedScalar *du = in[0], *qd = in[1]; 43 44 // out[0] is output to multiply against gradient v, shape [2, nc=1, Q] 45 CeedScalar *dv = out[0]; 46 47 // Quadrature point loop 48 for (CeedInt i=0; i<Q; i++) { 49 const CeedScalar du0 = du[i+Q*0]; 50 const CeedScalar du1 = du[i+Q*1]; 51 dv[i+Q*0] = qd[i+Q*0]*du0 + qd[i+Q*2]*du1; 52 dv[i+Q*1] = qd[i+Q*2]*du0 + qd[i+Q*1]*du1; 53 } 54 55 return 0; 56 } 57