1 2 /* 3 Code for manipulating distributed regular arrays in parallel. 4 */ 5 6 #include <petsc/private/dmdaimpl.h> /*I "petscdmda.h" I*/ 7 8 /*@ 9 DMDAGetLogicalCoordinate - Returns a the i,j,k logical coordinate for the closest mesh point to a x,y,z point in the coordinates of the DMDA 10 11 Collective on da 12 13 Input Parameters: 14 + da - the distributed array 15 - x,y,z - the physical coordinates 16 17 Output Parameters: 18 + II, JJ, KK - the logical coordinate (-1 on processes that do not contain that point) 19 - X, Y, Z, - (optional) the coordinates of the located grid point 20 21 Level: advanced 22 23 Notes: 24 All processors that share the DMDA must call this with the same coordinate value 25 26 @*/ 27 PetscErrorCode DMDAGetLogicalCoordinate(DM da,PetscScalar x,PetscScalar y,PetscScalar z,PetscInt *II,PetscInt *JJ,PetscInt *KK,PetscScalar *X,PetscScalar *Y,PetscScalar *Z) 28 { 29 PetscErrorCode ierr; 30 Vec coors; 31 DM dacoors; 32 DMDACoor2d **c; 33 PetscInt i,j,xs,xm,ys,ym; 34 PetscReal d,D = PETSC_MAX_REAL,Dv; 35 PetscMPIInt rank,root; 36 37 PetscFunctionBegin; 38 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 1d DMDA"); 39 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 3d DMDA"); 40 41 *II = -1; 42 *JJ = -1; 43 44 ierr = DMGetCoordinateDM(da,&dacoors);CHKERRQ(ierr); 45 ierr = DMDAGetCorners(dacoors,&xs,&ys,NULL,&xm,&ym,NULL);CHKERRQ(ierr); 46 ierr = DMGetCoordinates(da,&coors);CHKERRQ(ierr); 47 ierr = DMDAVecGetArrayRead(dacoors,coors,&c);CHKERRQ(ierr); 48 for (j=ys; j<ys+ym; j++) { 49 for (i=xs; i<xs+xm; i++) { 50 d = PetscSqrtReal(PetscRealPart( (c[j][i].x - x)*(c[j][i].x - x) + (c[j][i].y - y)*(c[j][i].y - y) )); 51 if (d < D) { 52 D = d; 53 *II = i; 54 *JJ = j; 55 } 56 } 57 } 58 ierr = MPIU_Allreduce(&D,&Dv,1,MPIU_REAL,MPIU_MIN,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 59 if (D != Dv) { 60 *II = -1; 61 *JJ = -1; 62 rank = 0; 63 } else { 64 *X = c[*JJ][*II].x; 65 *Y = c[*JJ][*II].y; 66 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)da),&rank);CHKERRQ(ierr); 67 rank++; 68 } 69 ierr = MPIU_Allreduce(&rank,&root,1,MPI_INT,MPI_SUM,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 70 root--; 71 ierr = MPI_Bcast(X,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 72 ierr = MPI_Bcast(Y,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 73 ierr = DMDAVecRestoreArrayRead(dacoors,coors,&c);CHKERRQ(ierr); 74 PetscFunctionReturn(0); 75 } 76 77 /*@ 78 DMDAGetRay - Returns a vector on process zero that contains a row or column of the values in a DMDA vector 79 80 Collective on DMDA 81 82 Input Parameters: 83 + da - the distributed array 84 . vec - the vector 85 . dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 86 - gp - global grid point number in this direction 87 88 Output Parameters: 89 + newvec - the new vector that can hold the values (size zero on all processes except process 0) 90 - scatter - the VecScatter that will map from the original vector to the slice 91 92 Level: advanced 93 94 Notes: 95 All processors that share the DMDA must call this with the same gp value 96 97 @*/ 98 PetscErrorCode DMDAGetRay(DM da,DMDirection dir,PetscInt gp,Vec *newvec,VecScatter *scatter) 99 { 100 PetscMPIInt rank; 101 DM_DA *dd = (DM_DA*)da->data; 102 PetscErrorCode ierr; 103 IS is; 104 AO ao; 105 Vec vec; 106 PetscInt *indices,i,j; 107 108 PetscFunctionBegin; 109 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get slice from 3d DMDA"); 110 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject) da), &rank);CHKERRQ(ierr); 111 ierr = DMDAGetAO(da, &ao);CHKERRQ(ierr); 112 if (!rank) { 113 if (da->dim == 1) { 114 if (dir == DM_X) { 115 ierr = PetscMalloc1(dd->w, &indices);CHKERRQ(ierr); 116 indices[0] = dd->w*gp; 117 for (i = 1; i < dd->w; ++i) indices[i] = indices[i-1] + 1; 118 ierr = AOApplicationToPetsc(ao, dd->w, indices);CHKERRQ(ierr); 119 ierr = VecCreate(PETSC_COMM_SELF, newvec);CHKERRQ(ierr); 120 ierr = VecSetBlockSize(*newvec, dd->w);CHKERRQ(ierr); 121 ierr = VecSetSizes(*newvec, dd->w, PETSC_DETERMINE);CHKERRQ(ierr); 122 ierr = VecSetType(*newvec, VECSEQ);CHKERRQ(ierr); 123 ierr = ISCreateGeneral(PETSC_COMM_SELF, dd->w, indices, PETSC_OWN_POINTER, &is);CHKERRQ(ierr); 124 } else if (dir == DM_Y) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get Y slice from 1d DMDA"); 125 else SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_ARG_OUTOFRANGE, "Unknown DMDirection"); 126 } else { 127 if (dir == DM_Y) { 128 ierr = PetscMalloc1(dd->w*dd->M,&indices);CHKERRQ(ierr); 129 indices[0] = gp*dd->M*dd->w; 130 for (i=1; i<dd->M*dd->w; i++) indices[i] = indices[i-1] + 1; 131 132 ierr = AOApplicationToPetsc(ao,dd->M*dd->w,indices);CHKERRQ(ierr); 133 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 134 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 135 ierr = VecSetSizes(*newvec,dd->M*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 136 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 137 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->M,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 138 } else if (dir == DM_X) { 139 ierr = PetscMalloc1(dd->w*dd->N,&indices);CHKERRQ(ierr); 140 indices[0] = dd->w*gp; 141 for (j=1; j<dd->w; j++) indices[j] = indices[j-1] + 1; 142 for (i=1; i<dd->N; i++) { 143 indices[i*dd->w] = indices[i*dd->w-1] + dd->w*dd->M - dd->w + 1; 144 for (j=1; j<dd->w; j++) indices[i*dd->w + j] = indices[i*dd->w + j - 1] + 1; 145 } 146 ierr = AOApplicationToPetsc(ao,dd->w*dd->N,indices);CHKERRQ(ierr); 147 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 148 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 149 ierr = VecSetSizes(*newvec,dd->N*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 150 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 151 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->N,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 152 } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown DMDirection"); 153 } 154 } else { 155 ierr = VecCreateSeq(PETSC_COMM_SELF, 0, newvec);CHKERRQ(ierr); 156 ierr = ISCreateGeneral(PETSC_COMM_SELF, 0, 0, PETSC_COPY_VALUES, &is);CHKERRQ(ierr); 157 } 158 ierr = DMGetGlobalVector(da, &vec);CHKERRQ(ierr); 159 ierr = VecScatterCreate(vec, is, *newvec, NULL, scatter);CHKERRQ(ierr); 160 ierr = DMRestoreGlobalVector(da, &vec);CHKERRQ(ierr); 161 ierr = ISDestroy(&is);CHKERRQ(ierr); 162 PetscFunctionReturn(0); 163 } 164 165 /*@C 166 DMDAGetProcessorSubset - Returns a communicator consisting only of the 167 processors in a DMDA that own a particular global x, y, or z grid point 168 (corresponding to a logical plane in a 3D grid or a line in a 2D grid). 169 170 Collective on da 171 172 Input Parameters: 173 + da - the distributed array 174 . dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 175 - gp - global grid point number in this direction 176 177 Output Parameters: 178 . comm - new communicator 179 180 Level: advanced 181 182 Notes: 183 All processors that share the DMDA must call this with the same gp value 184 185 After use, comm should be freed with MPI_Comm_free() 186 187 This routine is particularly useful to compute boundary conditions 188 or other application-specific calculations that require manipulating 189 sets of data throughout a logical plane of grid points. 190 191 Not supported from Fortran 192 193 @*/ 194 PetscErrorCode DMDAGetProcessorSubset(DM da,DMDirection dir,PetscInt gp,MPI_Comm *comm) 195 { 196 MPI_Group group,subgroup; 197 PetscErrorCode ierr; 198 PetscInt i,ict,flag,*owners,xs,xm,ys,ym,zs,zm; 199 PetscMPIInt size,*ranks = NULL; 200 DM_DA *dd = (DM_DA*)da->data; 201 202 PetscFunctionBegin; 203 PetscValidHeaderSpecificType(da,DM_CLASSID,1,DMDA); 204 flag = 0; 205 ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr); 206 ierr = MPI_Comm_size(PetscObjectComm((PetscObject)da),&size);CHKERRQ(ierr); 207 if (dir == DM_Z) { 208 if (da->dim < 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DM_Z invalid for DMDA dim < 3"); 209 if (gp < 0 || gp > dd->P) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 210 if (gp >= zs && gp < zs+zm) flag = 1; 211 } else if (dir == DM_Y) { 212 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DM_Y invalid for DMDA dim = 1"); 213 if (gp < 0 || gp > dd->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 214 if (gp >= ys && gp < ys+ym) flag = 1; 215 } else if (dir == DM_X) { 216 if (gp < 0 || gp > dd->M) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 217 if (gp >= xs && gp < xs+xm) flag = 1; 218 } else SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"Invalid direction"); 219 220 ierr = PetscMalloc2(size,&owners,size,&ranks);CHKERRQ(ierr); 221 ierr = MPI_Allgather(&flag,1,MPIU_INT,owners,1,MPIU_INT,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 222 ict = 0; 223 ierr = PetscInfo2(da,"DMDAGetProcessorSubset: dim=%D, direction=%d, procs: ",da->dim,(int)dir);CHKERRQ(ierr); 224 for (i=0; i<size; i++) { 225 if (owners[i]) { 226 ranks[ict] = i; ict++; 227 ierr = PetscInfo1(da,"%D ",i);CHKERRQ(ierr); 228 } 229 } 230 ierr = PetscInfo(da,"\n");CHKERRQ(ierr); 231 ierr = MPI_Comm_group(PetscObjectComm((PetscObject)da),&group);CHKERRQ(ierr); 232 ierr = MPI_Group_incl(group,ict,ranks,&subgroup);CHKERRQ(ierr); 233 ierr = MPI_Comm_create(PetscObjectComm((PetscObject)da),subgroup,comm);CHKERRQ(ierr); 234 ierr = MPI_Group_free(&subgroup);CHKERRQ(ierr); 235 ierr = MPI_Group_free(&group);CHKERRQ(ierr); 236 ierr = PetscFree2(owners,ranks);CHKERRQ(ierr); 237 PetscFunctionReturn(0); 238 } 239 240 /*@C 241 DMDAGetProcessorSubsets - Returns communicators consisting only of the 242 processors in a DMDA adjacent in a particular dimension, 243 corresponding to a logical plane in a 3D grid or a line in a 2D grid. 244 245 Collective on da 246 247 Input Parameters: 248 + da - the distributed array 249 - dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 250 251 Output Parameters: 252 . subcomm - new communicator 253 254 Level: advanced 255 256 Notes: 257 This routine is useful for distributing one-dimensional data in a tensor product grid. 258 259 After use, comm should be freed with MPI_Comm_free() 260 261 Not supported from Fortran 262 263 @*/ 264 PetscErrorCode DMDAGetProcessorSubsets(DM da, DMDirection dir, MPI_Comm *subcomm) 265 { 266 MPI_Comm comm; 267 MPI_Group group, subgroup; 268 PetscInt subgroupSize = 0; 269 PetscInt *firstPoints; 270 PetscMPIInt size, *subgroupRanks = NULL; 271 PetscInt xs, xm, ys, ym, zs, zm, firstPoint, p; 272 PetscErrorCode ierr; 273 274 PetscFunctionBegin; 275 PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA); 276 ierr = PetscObjectGetComm((PetscObject)da,&comm);CHKERRQ(ierr); 277 ierr = DMDAGetCorners(da, &xs, &ys, &zs, &xm, &ym, &zm);CHKERRQ(ierr); 278 ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr); 279 if (dir == DM_Z) { 280 if (da->dim < 3) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DM_Z invalid for DMDA dim < 3"); 281 firstPoint = zs; 282 } else if (dir == DM_Y) { 283 if (da->dim == 1) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DM_Y invalid for DMDA dim = 1"); 284 firstPoint = ys; 285 } else if (dir == DM_X) { 286 firstPoint = xs; 287 } else SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"Invalid direction"); 288 289 ierr = PetscMalloc2(size, &firstPoints, size, &subgroupRanks);CHKERRQ(ierr); 290 ierr = MPI_Allgather(&firstPoint, 1, MPIU_INT, firstPoints, 1, MPIU_INT, comm);CHKERRQ(ierr); 291 ierr = PetscInfo2(da,"DMDAGetProcessorSubset: dim=%D, direction=%d, procs: ",da->dim,(int)dir);CHKERRQ(ierr); 292 for (p = 0; p < size; ++p) { 293 if (firstPoints[p] == firstPoint) { 294 subgroupRanks[subgroupSize++] = p; 295 ierr = PetscInfo1(da, "%D ", p);CHKERRQ(ierr); 296 } 297 } 298 ierr = PetscInfo(da, "\n");CHKERRQ(ierr); 299 ierr = MPI_Comm_group(comm, &group);CHKERRQ(ierr); 300 ierr = MPI_Group_incl(group, subgroupSize, subgroupRanks, &subgroup);CHKERRQ(ierr); 301 ierr = MPI_Comm_create(comm, subgroup, subcomm);CHKERRQ(ierr); 302 ierr = MPI_Group_free(&subgroup);CHKERRQ(ierr); 303 ierr = MPI_Group_free(&group);CHKERRQ(ierr); 304 ierr = PetscFree2(firstPoints, subgroupRanks);CHKERRQ(ierr); 305 PetscFunctionReturn(0); 306 } 307