xref: /libCEED/examples/petsc/qfunctions/bps/bp2sphere.h (revision e3bad73b6850d4a62144dff4ac67aa0e734e1c96)
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 mass operator example for a vector field on the sphere using PETSc
19 
20 #ifndef bp2sphere_h
21 #define bp2sphere_h
22 #include <ceed.h>
23 
24 #ifndef __CUDACC__
25 #  include <math.h>
26 #endif
27 
28 // *****************************************************************************
29 // This QFunction sets up the rhs and true solution for the problem
30 // *****************************************************************************
31 
32 // -----------------------------------------------------------------------------
33 CEED_QFUNCTION(SetupMassRhs3)(void *ctx, const CeedInt Q,
34                              const CeedScalar *const *in,
35                              CeedScalar *const *out) {
36   // Inputs
37   const CeedScalar *X = in[0], *qdata = in[1];
38   // Outputs
39   CeedScalar *true_soln = out[0], *rhs = out[1];
40 
41   // Context
42   const CeedScalar *context = (const CeedScalar*)ctx;
43   const CeedScalar R        = context[0];
44 
45   // Quadrature Point Loop
46   CeedPragmaSIMD
47   for (CeedInt i=0; i<Q; i++) {
48     // Compute latitude
49     const CeedScalar theta =  asin(X[i+2*Q] / R);
50 
51     // Use absolute value of latitute for true solution
52     // Component 1
53     true_soln[i+0*Q] = fabs(theta);
54     // Component 2
55     true_soln[i+1*Q] = 2 * true_soln[i+0*Q];
56     // Component 3
57     true_soln[i+2*Q] = 3 * true_soln[i+0*Q];
58 
59     // Component 1
60     rhs[i+0*Q] = qdata[i] * true_soln[i];
61     // Component 2
62     rhs[i+1*Q] = 2 * rhs[i+0*Q];
63     // Component 3
64     rhs[i+2*Q] = 3 * rhs[i+0*Q];
65   } // End of Quadrature Point Loop
66 
67   return 0;
68 }
69 
70 // *****************************************************************************
71 // This QFunction applies the mass operator for a vector field of 3 components.
72 //
73 // Inputs:
74 //   u     - Input vector at quadrature points
75 //   qdata - Geometric factors
76 //
77 // Output:
78 //   v     - Output vector (test functions) at quadrature points
79 //
80 // *****************************************************************************
81 
82 // -----------------------------------------------------------------------------
83 CEED_QFUNCTION(Mass3)(void *ctx, const CeedInt Q,
84                       const CeedScalar *const *in, CeedScalar *const *out) {
85   const CeedScalar *u = in[0], *qdata = in[1];
86   CeedScalar *v = out[0];
87 
88   // Quadrature Point Loop
89   CeedPragmaSIMD
90   for (CeedInt i=0; i<Q; i++) {
91     const CeedScalar r = qdata[i];
92     // Component 1
93     v[i+0*Q] = r * u[i+0*Q];
94     // Component 2
95     v[i+1*Q] = r * u[i+1*Q];
96     // Component 3
97     v[i+2*Q] = r * u[i+2*Q];
98   } // End of Quadrature Point Loop
99 
100   return 0;
101 }
102 // -----------------------------------------------------------------------------
103 
104 #endif // bp2sphere_h
105