xref: /libCEED/examples/fluids/qfunctions/utils.h (revision 650a5d66e4f30da5db797426ea50232309c53955)
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 #ifndef utils_h
9 #define utils_h
10 
11 #include <ceed.h>
12 #include <math.h>
13 
14 #ifndef M_PI
15 #define M_PI 3.14159265358979323846
16 #endif
17 
18 CEED_QFUNCTION_HELPER CeedScalar Max(CeedScalar a, CeedScalar b) { return a < b ? b : a; }
19 CEED_QFUNCTION_HELPER CeedScalar Min(CeedScalar a, CeedScalar b) { return a < b ? a : b; }
20 
21 CEED_QFUNCTION_HELPER void SwapScalar(CeedScalar *a, CeedScalar *b) {
22   CeedScalar temp = *a;
23   *a              = *b;
24   *b              = temp;
25 }
26 
27 CEED_QFUNCTION_HELPER CeedScalar Square(CeedScalar x) { return x * x; }
28 CEED_QFUNCTION_HELPER CeedScalar Cube(CeedScalar x) { return x * x * x; }
29 
30 // @brief Scale vector of length N by scalar alpha
31 CEED_QFUNCTION_HELPER void ScaleN(CeedScalar *u, const CeedScalar alpha, const CeedInt N) {
32   CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) u[i] *= alpha;
33 }
34 
35 // @brief Set vector of length N to a value alpha
36 CEED_QFUNCTION_HELPER void SetValueN(CeedScalar *u, const CeedScalar alpha, const CeedInt N) {
37   CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) u[i] = alpha;
38 }
39 
40 // @brief Copy N elements from x to y
41 CEED_QFUNCTION_HELPER void CopyN(const CeedScalar *x, CeedScalar *y, const CeedInt N) { CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) y[i] = x[i]; }
42 
43 // @brief Copy 3x3 matrix from A to B
44 CEED_QFUNCTION_HELPER void CopyMat3(const CeedScalar A[3][3], CeedScalar B[3][3]) { CopyN((const CeedScalar *)A, (CeedScalar *)B, 9); }
45 
46 // @brief Dot product of vectors with N elements
47 CEED_QFUNCTION_HELPER CeedScalar DotN(const CeedScalar *u, const CeedScalar *v, const CeedInt N) {
48   CeedScalar output = 0;
49   CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) output += u[i] * v[i];
50   return output;
51 }
52 
53 // @brief Dot product of 3 element vectors
54 CEED_QFUNCTION_HELPER CeedScalar Dot3(const CeedScalar *u, const CeedScalar *v) { return u[0] * v[0] + u[1] * v[1] + u[2] * v[2]; }
55 
56 // @brief Cross product of vectors with 3 elements
57 CEED_QFUNCTION_HELPER void Cross3(const CeedScalar u[3], const CeedScalar v[3], CeedScalar w[3]) {
58   w[0] = (u[1] * v[2]) - (u[2] * v[1]);
59   w[1] = (u[2] * v[0]) - (u[0] * v[2]);
60   w[2] = (u[0] * v[1]) - (u[1] * v[0]);
61 }
62 
63 // @brief Curl of vector given its gradient
64 CEED_QFUNCTION_HELPER void Curl3(const CeedScalar gradient[3][3], CeedScalar v[3]) {
65   v[0] = gradient[2][1] - gradient[1][2];
66   v[1] = gradient[0][2] - gradient[2][0];
67   v[2] = gradient[1][0] - gradient[0][1];
68 }
69 
70 // @brief Matrix vector product, b = Ax + b. A is NxM, x is M, b is N
71 CEED_QFUNCTION_HELPER void MatVecNM(const CeedScalar *A, const CeedScalar *x, const CeedInt N, const CeedInt M, const CeedTransposeMode transpose_A,
72                                     CeedScalar *b) {
73   switch (transpose_A) {
74     case CEED_NOTRANSPOSE:
75       CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) b[i] += DotN(&A[i * M], x, M);
76       break;
77     case CEED_TRANSPOSE:
78       CeedPragmaSIMD for (CeedInt i = 0; i < M; i++) { CeedPragmaSIMD for (CeedInt j = 0; j < N; j++) b[i] += A[j * M + i] * x[j]; }
79       break;
80   }
81 }
82 
83 // @brief 3x3 Matrix vector product  b = Ax + b.
84 CEED_QFUNCTION_HELPER void MatVec3(const CeedScalar A[3][3], const CeedScalar x[3], const CeedTransposeMode transpose_A, CeedScalar b[3]) {
85   MatVecNM((const CeedScalar *)A, (const CeedScalar *)x, 3, 3, transpose_A, (CeedScalar *)b);
86 }
87 
88 // @brief Matrix-Matrix product, B = DA + B, where D is diagonal.
89 // @details A is NxM, D is diagonal NxN, represented by a vector of length N, and B is NxM. Optionally, A may be transposed.
90 CEED_QFUNCTION_HELPER void MatDiagNM(const CeedScalar *A, const CeedScalar *D, const CeedInt N, const CeedInt M, const CeedTransposeMode transpose_A,
91                                      CeedScalar *B) {
92   switch (transpose_A) {
93     case CEED_NOTRANSPOSE:
94       CeedPragmaSIMD for (CeedInt i = 0; i < N; i++) { CeedPragmaSIMD for (CeedInt j = 0; j < M; j++) B[i * M + j] += D[i] * A[i * M + j]; }
95       break;
96     case CEED_TRANSPOSE:
97       CeedPragmaSIMD for (CeedInt i = 0; i < M; i++) { CeedPragmaSIMD for (CeedInt j = 0; j < N; j++) B[i * N + j] += D[i] * A[j * M + i]; }
98       break;
99   }
100 }
101 
102 // @brief 3x3 Matrix-Matrix product, B = DA + B, where D is diagonal.
103 // @details Optionally, A may be transposed.
104 CEED_QFUNCTION_HELPER void MatDiag3(const CeedScalar A[3][3], const CeedScalar D[3], const CeedTransposeMode transpose_A, CeedScalar B[3][3]) {
105   MatDiagNM((const CeedScalar *)A, (const CeedScalar *)D, 3, 3, transpose_A, (CeedScalar *)B);
106 }
107 
108 // @brief 3x3 Matrix-Matrix product, C = AB + C
109 CEED_QFUNCTION_HELPER void MatMat3(const CeedScalar A[3][3], const CeedScalar B[3][3], const CeedTransposeMode transpose_A,
110                                    const CeedTransposeMode transpose_B, CeedScalar C[3][3]) {
111   switch (transpose_A) {
112     case CEED_NOTRANSPOSE:
113       switch (transpose_B) {
114         case CEED_NOTRANSPOSE:
115           CeedPragmaSIMD for (CeedInt i = 0; i < 3; i++) {
116             CeedPragmaSIMD for (CeedInt j = 0; j < 3; j++) { CeedPragmaSIMD for (CeedInt k = 0; k < 3; k++) C[i][j] += A[i][k] * B[k][j]; }
117           }
118           break;
119         case CEED_TRANSPOSE:
120           CeedPragmaSIMD for (CeedInt i = 0; i < 3; i++) {
121             CeedPragmaSIMD for (CeedInt j = 0; j < 3; j++) { CeedPragmaSIMD for (CeedInt k = 0; k < 3; k++) C[i][j] += A[i][k] * B[j][k]; }
122           }
123           break;
124       }
125       break;
126     case CEED_TRANSPOSE:
127       switch (transpose_B) {
128         case CEED_NOTRANSPOSE:
129           CeedPragmaSIMD for (CeedInt i = 0; i < 3; i++) {
130             CeedPragmaSIMD for (CeedInt j = 0; j < 3; j++) { CeedPragmaSIMD for (CeedInt k = 0; k < 3; k++) C[i][j] += A[k][i] * B[k][j]; }
131           }
132           break;
133         case CEED_TRANSPOSE:
134           CeedPragmaSIMD for (CeedInt i = 0; i < 3; i++) {
135             CeedPragmaSIMD for (CeedInt j = 0; j < 3; j++) { CeedPragmaSIMD for (CeedInt k = 0; k < 3; k++) C[i][j] += A[k][i] * B[j][k]; }
136           }
137           break;
138       }
139       break;
140   }
141 }
142 
143 // @brief Unpack Kelvin-Mandel notation symmetric tensor into full tensor
144 CEED_QFUNCTION_HELPER void KMUnpack(const CeedScalar v[6], CeedScalar A[3][3]) {
145   const CeedScalar weight = 1 / sqrt(2.);
146   A[0][0]                 = v[0];
147   A[1][1]                 = v[1];
148   A[2][2]                 = v[2];
149   A[2][1] = A[1][2] = weight * v[3];
150   A[2][0] = A[0][2] = weight * v[4];
151   A[1][0] = A[0][1] = weight * v[5];
152 }
153 
154 // @brief Pack full tensor into Kelvin-Mandel notation symmetric tensor
155 CEED_QFUNCTION_HELPER void KMPack(const CeedScalar A[3][3], CeedScalar v[6]) {
156   const CeedScalar weight = sqrt(2.);
157   v[0]                    = A[0][0];
158   v[1]                    = A[1][1];
159   v[2]                    = A[2][2];
160   v[3]                    = A[2][1] * weight;
161   v[4]                    = A[2][0] * weight;
162   v[5]                    = A[1][0] * weight;
163 }
164 
165 // @brief Calculate metric tensor from mapping, g_{ij} = xi_{k,i} xi_{k,j} = dXdx^T dXdx
166 CEED_QFUNCTION_HELPER void KMMetricTensor(const CeedScalar dXdx[3][3], CeedScalar km_g_ij[6]) {
167   CeedScalar g_ij[3][3] = {{0.}};
168   MatMat3(dXdx, dXdx, CEED_TRANSPOSE, CEED_NOTRANSPOSE, g_ij);
169   KMPack(g_ij, km_g_ij);
170 }
171 
172 // @brief Linear ramp evaluation
173 CEED_QFUNCTION_HELPER CeedScalar LinearRampCoefficient(CeedScalar amplitude, CeedScalar length, CeedScalar start, CeedScalar x) {
174   if (x < start) {
175     return amplitude;
176   } else if (x < start + length) {
177     return amplitude * ((x - start) * (-1 / length) + 1);
178   } else {
179     return 0;
180   }
181 }
182 
183 /**
184   @brief Pack stored values at quadrature point
185 
186   @param[in]   Q              Number of quadrature points
187   @param[in]   i              Current quadrature point
188   @param[in]   start          Starting index to store components
189   @param[in]   num_comp       Number of components to store
190   @param[in]   values_at_qpnt Local values for quadrature point i
191   @param[out]  stored         Stored values
192 
193   @return An error code: 0 - success, otherwise - failure
194 **/
195 CEED_QFUNCTION_HELPER int StoredValuesPack(CeedInt Q, CeedInt i, CeedInt start, CeedInt num_comp, const CeedScalar *values_at_qpnt,
196                                            CeedScalar *stored) {
197   for (CeedInt j = 0; j < num_comp; j++) stored[(start + j) * Q + i] = values_at_qpnt[j];
198 
199   return CEED_ERROR_SUCCESS;
200 }
201 
202 /**
203   @brief Unpack stored values at quadrature point
204 
205   @param[in]   Q              Number of quadrature points
206   @param[in]   i              Current quadrature point
207   @param[in]   start          Starting index to store components
208   @param[in]   num_comp       Number of components to store
209   @param[in]   stored         Stored values
210   @param[out]  values_at_qpnt Local values for quadrature point i
211 
212   @return An error code: 0 - success, otherwise - failure
213 **/
214 CEED_QFUNCTION_HELPER int StoredValuesUnpack(CeedInt Q, CeedInt i, CeedInt start, CeedInt num_comp, const CeedScalar *stored,
215                                              CeedScalar *values_at_qpnt) {
216   for (CeedInt j = 0; j < num_comp; j++) values_at_qpnt[j] = stored[(start + j) * Q + i];
217 
218   return CEED_ERROR_SUCCESS;
219 }
220 
221 /**
222   @brief Unpack 3D element q_data at quadrature point
223 
224   @param[in]   Q         Number of quadrature points
225   @param[in]   i         Current quadrature point
226   @param[in]   q_data    Pointer to q_data (generated by `setupgeo.h:Setup`)
227   @param[out]  wdetJ     Quadrature weight times determinant of the mapping Jacobian
228   @param[out]  dXdx      Inverse of the mapping Jacobian (shape [3][3])
229 
230   @return An error code: 0 - success, otherwise - failure
231 **/
232 CEED_QFUNCTION_HELPER int QdataUnpack_3D(CeedInt Q, CeedInt i, const CeedScalar *q_data, CeedScalar *wdetJ, CeedScalar dXdx[3][3]) {
233   StoredValuesUnpack(Q, i, 0, 1, q_data, wdetJ);
234   StoredValuesUnpack(Q, i, 1, 9, q_data, (CeedScalar *)dXdx);
235   return CEED_ERROR_SUCCESS;
236 }
237 
238 /**
239   @brief Unpack boundary element q_data for 3D problem at quadrature point
240 
241   @param[in]   Q         Number of quadrature points
242   @param[in]   i         Current quadrature point
243   @param[in]   q_data    Pointer to q_data (generated by `setupgeo.h:Setup`)
244   @param[out]  wdetJ     Quadrature weight times determinant of the mapping Jacobian, or `NULL`
245   @param[out]  dXdx      Inverse of the mapping Jacobian (shape [2][3]), or `NULL`
246   @param[out]  normal    Components of the normal vector (shape [3]), or `NULL`
247 
248   @return An error code: 0 - success, otherwise - failure
249 **/
250 CEED_QFUNCTION_HELPER int QdataBoundaryUnpack_3D(CeedInt Q, CeedInt i, const CeedScalar *q_data, CeedScalar *wdetJ, CeedScalar dXdx[2][3],
251                                                  CeedScalar normal[3]) {
252   if (wdetJ) StoredValuesUnpack(Q, i, 0, 1, q_data, wdetJ);
253   if (normal) StoredValuesUnpack(Q, i, 1, 3, q_data, normal);
254   if (dXdx) StoredValuesUnpack(Q, i, 4, 6, q_data, (CeedScalar *)dXdx);
255   return CEED_ERROR_SUCCESS;
256 }
257 
258 #endif  // utils_h
259