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 #undef __FUNCT__ 9 #define __FUNCT__ "DMDAGetLogicalCoordinate" 10 /*@C 11 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 12 13 Collective on DMDA 14 15 Input Parameters: 16 + da - the distributed array 17 - x,y,z - the physical coordinates 18 19 Output Parameters: 20 + II, JJ, KK - the logical coordinate (-1 on processes that do not contain that point) 21 - X, Y, Z, - (optional) the coordinates of the located grid point 22 23 Level: advanced 24 25 Notes: 26 All processors that share the DMDA must call this with the same coordinate value 27 28 .keywords: distributed array, get, processor subset 29 @*/ 30 PetscErrorCode DMDAGetLogicalCoordinate(DM da,PetscScalar x,PetscScalar y,PetscScalar z,PetscInt *II,PetscInt *JJ,PetscInt *KK,PetscScalar *X,PetscScalar *Y,PetscScalar *Z) 31 { 32 PetscErrorCode ierr; 33 Vec coors; 34 DM dacoors; 35 DMDACoor2d **c; 36 PetscInt i,j,xs,xm,ys,ym; 37 PetscReal d,D = PETSC_MAX_REAL,Dv; 38 PetscMPIInt rank,root; 39 40 PetscFunctionBegin; 41 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 1d DMDA"); 42 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_SUP,"Cannot get point from 3d DMDA"); 43 44 *II = -1; 45 *JJ = -1; 46 47 ierr = DMGetCoordinateDM(da,&dacoors);CHKERRQ(ierr); 48 ierr = DMDAGetCorners(dacoors,&xs,&ys,NULL,&xm,&ym,NULL);CHKERRQ(ierr); 49 ierr = DMGetCoordinates(da,&coors);CHKERRQ(ierr); 50 ierr = DMDAVecGetArray(dacoors,coors,&c);CHKERRQ(ierr); 51 for (j=ys; j<ys+ym; j++) { 52 for (i=xs; i<xs+xm; i++) { 53 d = PetscSqrtReal(PetscRealPart( (c[j][i].x - x)*(c[j][i].x - x) + (c[j][i].y - y)*(c[j][i].y - y) )); 54 if (d < D) { 55 D = d; 56 *II = i; 57 *JJ = j; 58 } 59 } 60 } 61 ierr = MPI_Allreduce(&D,&Dv,1,MPIU_REAL,MPI_MIN,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 62 if (D != Dv) { 63 *II = -1; 64 *JJ = -1; 65 rank = 0; 66 } else { 67 *X = c[*JJ][*II].x; 68 *Y = c[*JJ][*II].y; 69 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)da),&rank);CHKERRQ(ierr); 70 rank++; 71 } 72 ierr = MPI_Allreduce(&rank,&root,1,MPI_INT,MPI_SUM,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 73 root--; 74 ierr = MPI_Bcast(X,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 75 ierr = MPI_Bcast(Y,1,MPIU_SCALAR,root,PetscObjectComm((PetscObject)da));CHKERRQ(ierr); 76 ierr = DMDAVecRestoreArray(dacoors,coors,&c);CHKERRQ(ierr); 77 PetscFunctionReturn(0); 78 } 79 80 #undef __FUNCT__ 81 #define __FUNCT__ "DMDAGetRay" 82 /*@C 83 DMDAGetRay - Returns a vector on process zero that contains a row or column of the values in a DMDA vector 84 85 Collective on DMDA 86 87 Input Parameters: 88 + da - the distributed array 89 . vec - the vector 90 . dir - Cartesian direction, either DMDA_X, DMDA_Y, or DMDA_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 .keywords: distributed array, get, processor subset 103 @*/ 104 PetscErrorCode DMDAGetRay(DM da,DMDADirection dir,PetscInt gp,Vec *newvec,VecScatter *scatter) 105 { 106 PetscMPIInt rank; 107 DM_DA *dd = (DM_DA*)da->data; 108 PetscErrorCode ierr; 109 IS is; 110 AO ao; 111 Vec vec; 112 PetscInt *indices,i,j; 113 114 PetscFunctionBegin; 115 if (da->dim == 3) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get slice from 3d DMDA"); 116 ierr = MPI_Comm_rank(PetscObjectComm((PetscObject) da), &rank);CHKERRQ(ierr); 117 ierr = DMDAGetAO(da, &ao);CHKERRQ(ierr); 118 if (!rank) { 119 if (da->dim == 1) { 120 if (dir == DMDA_X) { 121 ierr = PetscMalloc1(dd->w, &indices);CHKERRQ(ierr); 122 indices[0] = dd->w*gp; 123 for (i = 1; i < dd->w; ++i) indices[i] = indices[i-1] + 1; 124 ierr = AOApplicationToPetsc(ao, dd->w, indices);CHKERRQ(ierr); 125 ierr = VecCreate(PETSC_COMM_SELF, newvec);CHKERRQ(ierr); 126 ierr = VecSetBlockSize(*newvec, dd->w);CHKERRQ(ierr); 127 ierr = VecSetSizes(*newvec, dd->w, PETSC_DETERMINE);CHKERRQ(ierr); 128 ierr = VecSetType(*newvec, VECSEQ);CHKERRQ(ierr); 129 ierr = ISCreateGeneral(PETSC_COMM_SELF, dd->w, indices, PETSC_OWN_POINTER, &is);CHKERRQ(ierr); 130 } else if (dir == DMDA_Y) SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_SUP, "Cannot get Y slice from 1d DMDA"); 131 else SETERRQ(PetscObjectComm((PetscObject) da), PETSC_ERR_ARG_OUTOFRANGE, "Unknown DMDADirection"); 132 } else { 133 if (dir == DMDA_Y) { 134 ierr = PetscMalloc1(dd->w*dd->M,&indices);CHKERRQ(ierr); 135 indices[0] = gp*dd->M*dd->w; 136 for (i=1; i<dd->M*dd->w; i++) indices[i] = indices[i-1] + 1; 137 138 ierr = AOApplicationToPetsc(ao,dd->M*dd->w,indices);CHKERRQ(ierr); 139 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 140 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 141 ierr = VecSetSizes(*newvec,dd->M*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 142 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 143 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->M,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 144 } else if (dir == DMDA_X) { 145 ierr = PetscMalloc1(dd->w*dd->N,&indices);CHKERRQ(ierr); 146 indices[0] = dd->w*gp; 147 for (j=1; j<dd->w; j++) indices[j] = indices[j-1] + 1; 148 for (i=1; i<dd->N; i++) { 149 indices[i*dd->w] = indices[i*dd->w-1] + dd->w*dd->M - dd->w + 1; 150 for (j=1; j<dd->w; j++) indices[i*dd->w + j] = indices[i*dd->w + j - 1] + 1; 151 } 152 ierr = AOApplicationToPetsc(ao,dd->w*dd->N,indices);CHKERRQ(ierr); 153 ierr = VecCreate(PETSC_COMM_SELF,newvec);CHKERRQ(ierr); 154 ierr = VecSetBlockSize(*newvec,dd->w);CHKERRQ(ierr); 155 ierr = VecSetSizes(*newvec,dd->N*dd->w,PETSC_DETERMINE);CHKERRQ(ierr); 156 ierr = VecSetType(*newvec,VECSEQ);CHKERRQ(ierr); 157 ierr = ISCreateGeneral(PETSC_COMM_SELF,dd->w*dd->N,indices,PETSC_OWN_POINTER,&is);CHKERRQ(ierr); 158 } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown DMDADirection"); 159 } 160 } else { 161 ierr = VecCreateSeq(PETSC_COMM_SELF, 0, newvec);CHKERRQ(ierr); 162 ierr = ISCreateGeneral(PETSC_COMM_SELF, 0, 0, PETSC_COPY_VALUES, &is);CHKERRQ(ierr); 163 } 164 ierr = DMGetGlobalVector(da, &vec);CHKERRQ(ierr); 165 ierr = VecScatterCreate(vec, is, *newvec, NULL, scatter);CHKERRQ(ierr); 166 ierr = DMRestoreGlobalVector(da, &vec);CHKERRQ(ierr); 167 ierr = ISDestroy(&is);CHKERRQ(ierr); 168 PetscFunctionReturn(0); 169 } 170 171 #undef __FUNCT__ 172 #define __FUNCT__ "DMDAGetProcessorSubset" 173 /*@C 174 DMDAGetProcessorSubset - Returns a communicator consisting only of the 175 processors in a DMDA that own a particular global x, y, or z grid point 176 (corresponding to a logical plane in a 3D grid or a line in a 2D grid). 177 178 Collective on DMDA 179 180 Input Parameters: 181 + da - the distributed array 182 . dir - Cartesian direction, either DMDA_X, DMDA_Y, or DMDA_Z 183 - gp - global grid point number in this direction 184 185 Output Parameters: 186 . comm - new communicator 187 188 Level: advanced 189 190 Notes: 191 All processors that share the DMDA must call this with the same gp value 192 193 This routine is particularly useful to compute boundary conditions 194 or other application-specific calculations that require manipulating 195 sets of data throughout a logical plane of grid points. 196 197 .keywords: distributed array, get, processor subset 198 @*/ 199 PetscErrorCode DMDAGetProcessorSubset(DM da,DMDADirection 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 PetscValidHeaderSpecific(da,DM_CLASSID,1); 209 flag = 0; 210 ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr); 211 ierr = MPI_Comm_size(PetscObjectComm((PetscObject)da),&size);CHKERRQ(ierr); 212 if (dir == DMDA_Z) { 213 if (da->dim < 3) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DMDA_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 == DMDA_Y) { 217 if (da->dim == 1) SETERRQ(PetscObjectComm((PetscObject)da),PETSC_ERR_ARG_OUTOFRANGE,"DMDA_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 == DMDA_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));CHKERRQ(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);CHKERRQ(ierr); 237 ierr = MPI_Group_incl(group,ict,ranks,&subgroup);CHKERRQ(ierr); 238 ierr = MPI_Comm_create(PetscObjectComm((PetscObject)da),subgroup,comm);CHKERRQ(ierr); 239 ierr = MPI_Group_free(&subgroup);CHKERRQ(ierr); 240 ierr = MPI_Group_free(&group);CHKERRQ(ierr); 241 ierr = PetscFree2(owners,ranks);CHKERRQ(ierr); 242 PetscFunctionReturn(0); 243 } 244 245 #undef __FUNCT__ 246 #define __FUNCT__ "DMDAGetProcessorSubsets" 247 /*@C 248 DMDAGetProcessorSubsets - Returns communicators consisting only of the 249 processors in a DMDA adjacent in a particular dimension, 250 corresponding to a logical plane in a 3D grid or a line in a 2D grid. 251 252 Collective on DMDA 253 254 Input Parameters: 255 + da - the distributed array 256 - dir - Cartesian direction, either DMDA_X, DMDA_Y, or DMDA_Z 257 258 Output Parameters: 259 . subcomm - new communicator 260 261 Level: advanced 262 263 Notes: 264 This routine is useful for distributing one-dimensional data in a tensor product grid. 265 266 .keywords: distributed array, get, processor subset 267 @*/ 268 PetscErrorCode DMDAGetProcessorSubsets(DM da, DMDADirection dir, MPI_Comm *subcomm) 269 { 270 MPI_Comm comm; 271 MPI_Group group, subgroup; 272 PetscInt subgroupSize = 0; 273 PetscInt *firstPoints; 274 PetscMPIInt size, *subgroupRanks = NULL; 275 PetscInt xs, xm, ys, ym, zs, zm, firstPoint, p; 276 PetscErrorCode ierr; 277 278 PetscFunctionBegin; 279 PetscValidHeaderSpecific(da, DM_CLASSID, 1); 280 ierr = PetscObjectGetComm((PetscObject)da,&comm);CHKERRQ(ierr); 281 ierr = DMDAGetCorners(da, &xs, &ys, &zs, &xm, &ym, &zm);CHKERRQ(ierr); 282 ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr); 283 if (dir == DMDA_Z) { 284 if (da->dim < 3) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DMDA_Z invalid for DMDA dim < 3"); 285 firstPoint = zs; 286 } else if (dir == DMDA_Y) { 287 if (da->dim == 1) SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"DMDA_Y invalid for DMDA dim = 1"); 288 firstPoint = ys; 289 } else if (dir == DMDA_X) { 290 firstPoint = xs; 291 } else SETERRQ(comm,PETSC_ERR_ARG_OUTOFRANGE,"Invalid direction"); 292 293 ierr = PetscMalloc2(size, &firstPoints, size, &subgroupRanks);CHKERRQ(ierr); 294 ierr = MPI_Allgather(&firstPoint, 1, MPIU_INT, firstPoints, 1, MPIU_INT, comm);CHKERRQ(ierr); 295 ierr = PetscInfo2(da,"DMDAGetProcessorSubset: dim=%D, direction=%d, procs: ",da->dim,(int)dir);CHKERRQ(ierr); 296 for (p = 0; p < size; ++p) { 297 if (firstPoints[p] == firstPoint) { 298 subgroupRanks[subgroupSize++] = p; 299 ierr = PetscInfo1(da, "%D ", p);CHKERRQ(ierr); 300 } 301 } 302 ierr = PetscInfo(da, "\n");CHKERRQ(ierr); 303 ierr = MPI_Comm_group(comm, &group);CHKERRQ(ierr); 304 ierr = MPI_Group_incl(group, subgroupSize, subgroupRanks, &subgroup);CHKERRQ(ierr); 305 ierr = MPI_Comm_create(comm, subgroup, subcomm);CHKERRQ(ierr); 306 ierr = MPI_Group_free(&subgroup);CHKERRQ(ierr); 307 ierr = MPI_Group_free(&group);CHKERRQ(ierr); 308 ierr = PetscFree2(firstPoints, subgroupRanks);CHKERRQ(ierr); 309 PetscFunctionReturn(0); 310 } 311