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 - the first physical coordinate 16 . y - the second physical coordinate 17 - z - the third physical coordinate 18 19 Output Parameters: 20 + II - the first logical coordinate (-1 on processes that do not contain that point) 21 . JJ - the second logical coordinate (-1 on processes that do not contain that point) 22 . KK - the third logical coordinate (-1 on processes that do not contain that point) 23 . X - (optional) the first coordinate of the located grid point 24 . Y - (optional) the second coordinate of the located grid point 25 - Z - (optional) the third coordinate of the located grid point 26 27 Level: advanced 28 29 Notes: 30 All processors that share the DMDA must call this with the same coordinate value 31 32 @*/ 33 PetscErrorCode DMDAGetLogicalCoordinate(DM da,PetscScalar x,PetscScalar y,PetscScalar z,PetscInt *II,PetscInt *JJ,PetscInt *KK,PetscScalar *X,PetscScalar *Y,PetscScalar *Z) 34 { 35 PetscErrorCode ierr; 36 Vec coors; 37 DM dacoors; 38 DMDACoor2d **c; 39 PetscInt i,j,xs,xm,ys,ym; 40 PetscReal d,D = PETSC_MAX_REAL,Dv; 41 PetscMPIInt rank,root; 42 43 PetscFunctionBegin; 44 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 1d DMDA"); 45 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 3d DMDA"); 46 47 *II = -1; 48 *JJ = -1; 49 50 ierr = DMGetCoordinateDM(da,&dacoors);CHKERRQ(ierr); 51 ierr = DMDAGetCorners(dacoors,&xs,&ys,NULL,&xm,&ym,NULL);CHKERRQ(ierr); 52 ierr = DMGetCoordinates(da,&coors);CHKERRQ(ierr); 53 ierr = DMDAVecGetArrayRead(dacoors,coors,&c);CHKERRQ(ierr); 54 for (j=ys; j<ys+ym; j++) { 55 for (i=xs; i<xs+xm; i++) { 56 d = PetscSqrtReal(PetscRealPart((c[j][i].x - x)*(c[j][i].x - x) + (c[j][i].y - y)*(c[j][i].y - y))); 57 if (d < D) { 58 D = d; 59 *II = i; 60 *JJ = j; 61 } 62 } 63 } 64 ierr = MPIU_Allreduce(&D,&Dv,1,MPIU_REAL,MPIU_MIN,PetscObjectComm((PetscObject)da));CHKERRMPI(ierr); 65 if (D != Dv) { 66 *II = -1; 67 *JJ = -1; 68 rank = 0; 69 } else { 70 *X = c[*JJ][*II].x; 71 *Y = c[*JJ][*II].y; 72 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)da),&rank);CHKERRMPI(ierr); 73 rank++; 74 } 75 ierr = MPIU_Allreduce(&rank,&root,1,MPI_INT,MPI_SUM,PetscObjectComm((PetscObject)da));CHKERRMPI(ierr); 76 root--; 77 ierr = MPI_Bcast(X,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRMPI(ierr); 78 ierr = MPI_Bcast(Y,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRMPI(ierr); 79 ierr = DMDAVecRestoreArrayRead(dacoors,coors,&c);CHKERRQ(ierr); 80 PetscFunctionReturn(0); 81 } 82 83 /*@ 84 DMDAGetRay - Returns a vector on process zero that contains a row or column of the values in a DMDA vector 85 86 Collective on DMDA 87 88 Input Parameters: 89 + da - the distributed array 90 . dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 91 - gp - global grid point number in this direction 92 93 Output Parameters: 94 + newvec - the new vector that can hold the values (size zero on all processes except process 0) 95 - scatter - the VecScatter that will map from the original vector to the slice 96 97 Level: advanced 98 99 Notes: 100 All processors that share the DMDA must call this with the same gp value 101 102 @*/ 103 PetscErrorCode DMDAGetRay(DM da,DMDirection dir,PetscInt gp,Vec *newvec,VecScatter *scatter) 104 { 105 PetscMPIInt rank; 106 DM_DA *dd = (DM_DA*)da->data; 107 PetscErrorCode ierr; 108 IS is; 109 AO ao; 110 Vec vec; 111 PetscInt *indices,i,j; 112 113 PetscFunctionBegin; 114 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get slice from 3d DMDA"); 115 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject) da), &rank);CHKERRMPI(ierr); 116 ierr = DMDAGetAO(da, &ao);CHKERRQ(ierr); 117 if (rank == 0) { 118 if (da->dim == 1) { 119 if (dir == DM_X) { 120 ierr = PetscMalloc1(dd->w, &indices);CHKERRQ(ierr); 121 indices[0] = dd->w*gp; 122 for (i = 1; i < dd->w; ++i) indices[i] = indices[i-1] + 1; 123 ierr = AOApplicationToPetsc(ao, dd->w, indices);CHKERRQ(ierr); 124 ierr = VecCreate(PETSC_COMM_SELF, newvec);CHKERRQ(ierr); 125 ierr = VecSetBlockSize(*newvec, dd->w);CHKERRQ(ierr); 126 ierr = VecSetSizes(*newvec, dd->w, PETSC_DETERMINE);CHKERRQ(ierr); 127 ierr = VecSetType(*newvec, VECSEQ);CHKERRQ(ierr); 128 ierr = ISCreateGeneral(PETSC_COMM_SELF, dd->w, indices, PETSC_OWN_POINTER, &is);CHKERRQ(ierr); 129 } else if (dir == DM_Y) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get Y slice from 1d DMDA"); 130 else SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_ARG_OUTOFRANGE, "Unknown DMDirection"); 131 } else { 132 if (dir == DM_Y) { 133 ierr = PetscMalloc1(dd->w*dd->M,&indices);CHKERRQ(ierr); 134 indices[0] = gp*dd->M*dd->w; 135 for (i=1; i<dd->M*dd->w; i++) indices[i] = indices[i-1] + 1; 136 137 ierr = AOApplicationToPetsc(ao,dd->M*dd->w,indices);CHKERRQ(ierr); 138 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 139 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 140 ierr = VecSetSizes(*newvec,dd->M*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 141 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 142 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->M,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 143 } else if (dir == DM_X) { 144 ierr = PetscMalloc1(dd->w*dd->N,&indices);CHKERRQ(ierr); 145 indices[0] = dd->w*gp; 146 for (j=1; j<dd->w; j++) indices[j] = indices[j-1] + 1; 147 for (i=1; i<dd->N; i++) { 148 indices[i*dd->w] = indices[i*dd->w-1] + dd->w*dd->M - dd->w + 1; 149 for (j=1; j<dd->w; j++) indices[i*dd->w + j] = indices[i*dd->w + j - 1] + 1; 150 } 151 ierr = AOApplicationToPetsc(ao,dd->w*dd->N,indices);CHKERRQ(ierr); 152 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 153 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 154 ierr = VecSetSizes(*newvec,dd->N*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 155 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 156 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->N,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 157 } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown DMDirection"); 158 } 159 } else { 160 ierr = VecCreateSeq(PETSC_COMM_SELF, 0, newvec);CHKERRQ(ierr); 161 ierr = ISCreateGeneral(PETSC_COMM_SELF, 0, NULL, PETSC_COPY_VALUES, &is);CHKERRQ(ierr); 162 } 163 ierr = DMGetGlobalVector(da, &vec);CHKERRQ(ierr); 164 ierr = VecScatterCreate(vec, is, *newvec, NULL, scatter);CHKERRQ(ierr); 165 ierr = DMRestoreGlobalVector(da, &vec);CHKERRQ(ierr); 166 ierr = ISDestroy(&is);CHKERRQ(ierr); 167 PetscFunctionReturn(0); 168 } 169 170 /*@C 171 DMDAGetProcessorSubset - Returns a communicator consisting only of the 172 processors in a DMDA that own a particular global x, y, or z grid point 173 (corresponding to a logical plane in a 3D grid or a line in a 2D grid). 174 175 Collective on da 176 177 Input Parameters: 178 + da - the distributed array 179 . dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 180 - gp - global grid point number in this direction 181 182 Output Parameter: 183 . comm - new communicator 184 185 Level: advanced 186 187 Notes: 188 All processors that share the DMDA must call this with the same gp value 189 190 After use, comm should be freed with MPI_Comm_free() 191 192 This routine is particularly useful to compute boundary conditions 193 or other application-specific calculations that require manipulating 194 sets of data throughout a logical plane of grid points. 195 196 Not supported from Fortran 197 198 @*/ 199 PetscErrorCode DMDAGetProcessorSubset(DM da,DMDirection dir,PetscInt gp,MPI_Comm *comm) 200 { 201 MPI_Group group,subgroup; 202 PetscErrorCode ierr; 203 PetscInt i,ict,flag,*owners,xs,xm,ys,ym,zs,zm; 204 PetscMPIInt size,*ranks = NULL; 205 DM_DA *dd = (DM_DA*)da->data; 206 207 PetscFunctionBegin; 208 PetscValidHeaderSpecificType(da,DM_CLASSID,1,DMDA); 209 flag = 0; 210 ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr); 211 ierr = MPI_Comm_size(PetscObjectComm((PetscObject)da),&size);CHKERRMPI(ierr); 212 if (dir == DM_Z) { 213 if (da->dim < 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DM_Z invalid for DMDA dim < 3"); 214 if (gp < 0 || gp > dd->P) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 215 if (gp >= zs && gp < zs+zm) flag = 1; 216 } else if (dir == DM_Y) { 217 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DM_Y invalid for DMDA dim = 1"); 218 if (gp < 0 || gp > dd->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 219 if (gp >= ys && gp < ys+ym) flag = 1; 220 } else if (dir == DM_X) { 221 if (gp < 0 || gp > dd->M) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"invalid grid point"); 222 if (gp >= xs && gp < xs+xm) flag = 1; 223 } else SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"Invalid direction"); 224 225 ierr = PetscMalloc2(size,&owners,size,&ranks);CHKERRQ(ierr); 226 ierr = MPI_Allgather(&flag,1,MPIU_INT,owners,1,MPIU_INT,PetscObjectComm((PetscObject)da));CHKERRMPI(ierr); 227 ict = 0; 228 ierr = PetscInfo2(da,"DMDAGetProcessorSubset: dim=%D, direction=%d, procs: ",da->dim,(int)dir);CHKERRQ(ierr); 229 for (i=0; i<size; i++) { 230 if (owners[i]) { 231 ranks[ict] = i; ict++; 232 ierr = PetscInfo1(da,"%D ",i);CHKERRQ(ierr); 233 } 234 } 235 ierr = PetscInfo(da,"\n");CHKERRQ(ierr); 236 ierr = MPI_Comm_group(PetscObjectComm((PetscObject)da),&group);CHKERRMPI(ierr); 237 ierr = MPI_Group_incl(group,ict,ranks,&subgroup);CHKERRMPI(ierr); 238 ierr = MPI_Comm_create(PetscObjectComm((PetscObject)da),subgroup,comm);CHKERRMPI(ierr); 239 ierr = MPI_Group_free(&subgroup);CHKERRMPI(ierr); 240 ierr = MPI_Group_free(&group);CHKERRMPI(ierr); 241 ierr = PetscFree2(owners,ranks);CHKERRQ(ierr); 242 PetscFunctionReturn(0); 243 } 244 245 /*@C 246 DMDAGetProcessorSubsets - Returns communicators consisting only of the 247 processors in a DMDA adjacent in a particular dimension, 248 corresponding to a logical plane in a 3D grid or a line in a 2D grid. 249 250 Collective on da 251 252 Input Parameters: 253 + da - the distributed array 254 - dir - Cartesian direction, either DM_X, DM_Y, or DM_Z 255 256 Output Parameter: 257 . subcomm - new communicator 258 259 Level: advanced 260 261 Notes: 262 This routine is useful for distributing one-dimensional data in a tensor product grid. 263 264 After use, comm should be freed with MPI_Comm_free() 265 266 Not supported from Fortran 267 268 @*/ 269 PetscErrorCode DMDAGetProcessorSubsets(DM da, DMDirection dir, MPI_Comm *subcomm) 270 { 271 MPI_Comm comm; 272 MPI_Group group, subgroup; 273 PetscInt subgroupSize = 0; 274 PetscInt *firstPoints; 275 PetscMPIInt size, *subgroupRanks = NULL; 276 PetscInt xs, xm, ys, ym, zs, zm, firstPoint, p; 277 PetscErrorCode ierr; 278 279 PetscFunctionBegin; 280 PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA); 281 ierr = PetscObjectGetComm((PetscObject)da,&comm);CHKERRQ(ierr); 282 ierr = DMDAGetCorners(da, &xs, &ys, &zs, &xm, &ym, &zm);CHKERRQ(ierr); 283 ierr = MPI_Comm_size(comm, &size);CHKERRMPI(ierr); 284 if (dir == DM_Z) { 285 if (da->dim < 3) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DM_Z invalid for DMDA dim < 3"); 286 firstPoint = zs; 287 } else if (dir == DM_Y) { 288 if (da->dim == 1) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DM_Y invalid for DMDA dim = 1"); 289 firstPoint = ys; 290 } else if (dir == DM_X) { 291 firstPoint = xs; 292 } else SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"Invalid direction"); 293 294 ierr = PetscMalloc2(size, &firstPoints, size, &subgroupRanks);CHKERRQ(ierr); 295 ierr = MPI_Allgather(&firstPoint, 1, MPIU_INT, firstPoints, 1, MPIU_INT, comm);CHKERRMPI(ierr); 296 ierr = PetscInfo2(da,"DMDAGetProcessorSubset: dim=%D, direction=%d, procs: ",da->dim,(int)dir);CHKERRQ(ierr); 297 for (p = 0; p < size; ++p) { 298 if (firstPoints[p] == firstPoint) { 299 subgroupRanks[subgroupSize++] = p; 300 ierr = PetscInfo1(da, "%D ", p);CHKERRQ(ierr); 301 } 302 } 303 ierr = PetscInfo(da, "\n");CHKERRQ(ierr); 304 ierr = MPI_Comm_group(comm, &group);CHKERRMPI(ierr); 305 ierr = MPI_Group_incl(group, subgroupSize, subgroupRanks, &subgroup);CHKERRMPI(ierr); 306 ierr = MPI_Comm_create(comm, subgroup, subcomm);CHKERRMPI(ierr); 307 ierr = MPI_Group_free(&subgroup);CHKERRMPI(ierr); 308 ierr = MPI_Group_free(&group);CHKERRMPI(ierr); 309 ierr = PetscFree2(firstPoints, subgroupRanks);CHKERRQ(ierr); 310 PetscFunctionReturn(0); 311 } 312