Date: 2025-03-28T21:11:24+00:00

Actual source code: vinv.c

      1: /*
      2:      Some useful vector utility functions.
      3: */
      4: #include <../src/vec/vec/impls/mpi/pvecimpl.h>

      6: /*@
      7:   VecStrideSet - Sets a subvector of a vector defined
      8:   by a starting point and a stride with a given value

     10:   Logically Collective

     12:   Input Parameters:
     13: + v     - the vector
     14: . start - starting point of the subvector (defined by a stride)
     15: - s     - value to set for each entry in that subvector

     17:   Level: advanced

     19:   Notes:
     20:   One must call `VecSetBlockSize()` before this routine to set the stride
     21:   information, or use a vector created from a multicomponent `DMDA`.

     23:   This will only work if the desire subvector is a stride subvector

     25: .seealso: `Vec`, `VecNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideScale()`
     26: @*/
     27: PetscErrorCode VecStrideSet(Vec v, PetscInt start, PetscScalar s)
     28: {
     29:   PetscInt     i, n, bs;
     30:   PetscScalar *x;

     32:   PetscFunctionBegin;
     35:   PetscCall(VecGetLocalSize(v, &n));
     36:   PetscCall(VecGetBlockSize(v, &bs));
     37:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
     38:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
     39:   PetscCall(VecGetArray(v, &x));
     40:   for (i = start; i < n; i += bs) x[i] = s;
     41:   PetscCall(VecRestoreArray(v, &x));
     42:   PetscFunctionReturn(PETSC_SUCCESS);
     43: }

     45: /*@
     46:   VecStrideScale - Scales a subvector of a vector defined
     47:   by a starting point and a stride.

     49:   Logically Collective

     51:   Input Parameters:
     52: + v     - the vector
     53: . start - starting point of the subvector (defined by a stride)
     54: - scale - value to multiply each subvector entry by

     56:   Level: advanced

     58:   Notes:
     59:   One must call `VecSetBlockSize()` before this routine to set the stride
     60:   information, or use a vector created from a multicomponent `DMDA`.

     62:   This will only work if the desire subvector is a stride subvector

     64: .seealso: `Vec`, `VecNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
     65: @*/
     66: PetscErrorCode VecStrideScale(Vec v, PetscInt start, PetscScalar scale)
     67: {
     68:   PetscInt     i, n, bs;
     69:   PetscScalar *x;

     71:   PetscFunctionBegin;
     75:   PetscCall(VecGetLocalSize(v, &n));
     76:   PetscCall(VecGetBlockSize(v, &bs));
     77:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
     78:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
     79:   PetscCall(VecGetArray(v, &x));
     80:   for (i = start; i < n; i += bs) x[i] *= scale;
     81:   PetscCall(VecRestoreArray(v, &x));
     82:   PetscFunctionReturn(PETSC_SUCCESS);
     83: }

     85: /*@
     86:   VecStrideNorm - Computes the norm of subvector of a vector defined
     87:   by a starting point and a stride.

     89:   Collective

     91:   Input Parameters:
     92: + v     - the vector
     93: . start - starting point of the subvector (defined by a stride)
     94: - ntype - type of norm, one of `NORM_1`, `NORM_2`, `NORM_INFINITY`

     96:   Output Parameter:
     97: . nrm - the norm

     99:   Level: advanced

    101:   Notes:
    102:   One must call `VecSetBlockSize()` before this routine to set the stride
    103:   information, or use a vector created from a multicomponent `DMDA`.

    105:   If x is the array representing the vector x then this computes the norm
    106:   of the array (x[start],x[start+stride],x[start+2*stride], ....)

    108:   This is useful for computing, say the norm of the pressure variable when
    109:   the pressure is stored (interlaced) with other variables, say density etc.

    111:   This will only work if the desire subvector is a stride subvector

    113: .seealso: `Vec`, `VecNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
    114: @*/
    115: PetscErrorCode VecStrideNorm(Vec v, PetscInt start, NormType ntype, PetscReal *nrm)
    116: {
    117:   PetscInt           i, n, bs;
    118:   const PetscScalar *x;
    119:   PetscReal          tnorm;

    121:   PetscFunctionBegin;
    125:   PetscAssertPointer(nrm, 4);
    126:   PetscCall(VecGetLocalSize(v, &n));
    127:   PetscCall(VecGetBlockSize(v, &bs));
    128:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    129:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
    130:   PetscCall(VecGetArrayRead(v, &x));
    131:   if (ntype == NORM_2) {
    132:     PetscScalar sum = 0.0;
    133:     for (i = start; i < n; i += bs) sum += x[i] * (PetscConj(x[i]));
    134:     tnorm = PetscRealPart(sum);
    135:     PetscCallMPI(MPIU_Allreduce(&tnorm, nrm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)v)));
    136:     *nrm = PetscSqrtReal(*nrm);
    137:   } else if (ntype == NORM_1) {
    138:     tnorm = 0.0;
    139:     for (i = start; i < n; i += bs) tnorm += PetscAbsScalar(x[i]);
    140:     PetscCallMPI(MPIU_Allreduce(&tnorm, nrm, 1, MPIU_REAL, MPIU_SUM, PetscObjectComm((PetscObject)v)));
    141:   } else if (ntype == NORM_INFINITY) {
    142:     tnorm = 0.0;
    143:     for (i = start; i < n; i += bs) {
    144:       if (PetscAbsScalar(x[i]) > tnorm) tnorm = PetscAbsScalar(x[i]);
    145:     }
    146:     PetscCallMPI(MPIU_Allreduce(&tnorm, nrm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)v)));
    147:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");
    148:   PetscCall(VecRestoreArrayRead(v, &x));
    149:   PetscFunctionReturn(PETSC_SUCCESS);
    150: }

    152: /*@
    153:   VecStrideMax - Computes the maximum of subvector of a vector defined
    154:   by a starting point and a stride and optionally its location.

    156:   Collective

    158:   Input Parameters:
    159: + v     - the vector
    160: - start - starting point of the subvector (defined by a stride)

    162:   Output Parameters:
    163: + idex - the location where the maximum occurred  (pass `NULL` if not required)
    164: - nrm  - the maximum value in the subvector

    166:   Level: advanced

    168:   Notes:
    169:   One must call `VecSetBlockSize()` before this routine to set the stride
    170:   information, or use a vector created from a multicomponent `DMDA`.

    172:   If xa is the array representing the vector x, then this computes the max
    173:   of the array (xa[start],xa[start+stride],xa[start+2*stride], ....)

    175:   This is useful for computing, say the maximum of the pressure variable when
    176:   the pressure is stored (interlaced) with other variables, e.g., density, etc.
    177:   This will only work if the desire subvector is a stride subvector.

    179: .seealso: `Vec`, `VecMax()`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`
    180: @*/
    181: PetscErrorCode VecStrideMax(Vec v, PetscInt start, PetscInt *idex, PetscReal *nrm)
    182: {
    183:   PetscInt           i, n, bs, id = -1;
    184:   const PetscScalar *x;
    185:   PetscReal          max = PETSC_MIN_REAL;

    187:   PetscFunctionBegin;
    190:   PetscAssertPointer(nrm, 4);
    191:   PetscCall(VecGetLocalSize(v, &n));
    192:   PetscCall(VecGetBlockSize(v, &bs));
    193:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    194:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
    195:   PetscCall(VecGetArrayRead(v, &x));
    196:   for (i = start; i < n; i += bs) {
    197:     if (PetscRealPart(x[i]) > max) {
    198:       max = PetscRealPart(x[i]);
    199:       id  = i;
    200:     }
    201:   }
    202:   PetscCall(VecRestoreArrayRead(v, &x));
    203: #if defined(PETSC_HAVE_MPIUNI)
    204:   *nrm = max;
    205:   if (idex) *idex = id;
    206: #else
    207:   if (!idex) {
    208:     PetscCallMPI(MPIU_Allreduce(&max, nrm, 1, MPIU_REAL, MPIU_MAX, PetscObjectComm((PetscObject)v)));
    209:   } else {
    210:     struct {
    211:       PetscReal v;
    212:       PetscInt  i;
    213:     } in, out;
    214:     PetscInt rstart;

    216:     PetscCall(VecGetOwnershipRange(v, &rstart, NULL));
    217:     in.v = max;
    218:     in.i = rstart + id;
    219:     PetscCallMPI(MPIU_Allreduce(&in, &out, 1, MPIU_REAL_INT, MPIU_MAXLOC, PetscObjectComm((PetscObject)v)));
    220:     *nrm  = out.v;
    221:     *idex = out.i;
    222:   }
    223: #endif
    224:   PetscFunctionReturn(PETSC_SUCCESS);
    225: }

    227: /*@
    228:   VecStrideMin - Computes the minimum of subvector of a vector defined
    229:   by a starting point and a stride and optionally its location.

    231:   Collective

    233:   Input Parameters:
    234: + v     - the vector
    235: - start - starting point of the subvector (defined by a stride)

    237:   Output Parameters:
    238: + idex - the location where the minimum occurred. (pass `NULL` if not required)
    239: - nrm  - the minimum value in the subvector

    241:   Level: advanced

    243:   Notes:
    244:   One must call `VecSetBlockSize()` before this routine to set the stride
    245:   information, or use a vector created from a multicomponent `DMDA`.

    247:   If xa is the array representing the vector x, then this computes the min
    248:   of the array (xa[start],xa[start+stride],xa[start+2*stride], ....)

    250:   This is useful for computing, say the minimum of the pressure variable when
    251:   the pressure is stored (interlaced) with other variables, e.g., density, etc.
    252:   This will only work if the desire subvector is a stride subvector.

    254: .seealso: `Vec`, `VecMin()`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMax()`
    255: @*/
    256: PetscErrorCode VecStrideMin(Vec v, PetscInt start, PetscInt *idex, PetscReal *nrm)
    257: {
    258:   PetscInt           i, n, bs, id = -1;
    259:   const PetscScalar *x;
    260:   PetscReal          min = PETSC_MAX_REAL;

    262:   PetscFunctionBegin;
    265:   PetscAssertPointer(nrm, 4);
    266:   PetscCall(VecGetLocalSize(v, &n));
    267:   PetscCall(VecGetBlockSize(v, &bs));
    268:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    269:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
    270:   PetscCall(VecGetArrayRead(v, &x));
    271:   for (i = start; i < n; i += bs) {
    272:     if (PetscRealPart(x[i]) < min) {
    273:       min = PetscRealPart(x[i]);
    274:       id  = i;
    275:     }
    276:   }
    277:   PetscCall(VecRestoreArrayRead(v, &x));
    278: #if defined(PETSC_HAVE_MPIUNI)
    279:   *nrm = min;
    280:   if (idex) *idex = id;
    281: #else
    282:   if (!idex) {
    283:     PetscCallMPI(MPIU_Allreduce(&min, nrm, 1, MPIU_REAL, MPIU_MIN, PetscObjectComm((PetscObject)v)));
    284:   } else {
    285:     struct {
    286:       PetscReal v;
    287:       PetscInt  i;
    288:     } in, out;
    289:     PetscInt rstart;

    291:     PetscCall(VecGetOwnershipRange(v, &rstart, NULL));
    292:     in.v = min;
    293:     in.i = rstart + id;
    294:     PetscCallMPI(MPIU_Allreduce(&in, &out, 1, MPIU_REAL_INT, MPIU_MINLOC, PetscObjectComm((PetscObject)v)));
    295:     *nrm  = out.v;
    296:     *idex = out.i;
    297:   }
    298: #endif
    299:   PetscFunctionReturn(PETSC_SUCCESS);
    300: }

    302: /*@
    303:   VecStrideSum - Computes the sum of subvector of a vector defined
    304:   by a starting point and a stride.

    306:   Collective

    308:   Input Parameters:
    309: + v     - the vector
    310: - start - starting point of the subvector (defined by a stride)

    312:   Output Parameter:
    313: . sum - the sum

    315:   Level: advanced

    317:   Notes:
    318:   One must call `VecSetBlockSize()` before this routine to set the stride
    319:   information, or use a vector created from a multicomponent `DMDA`.

    321:   If x is the array representing the vector x then this computes the sum
    322:   of the array (x[start],x[start+stride],x[start+2*stride], ....)

    324: .seealso: `Vec`, `VecSum()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
    325: @*/
    326: PetscErrorCode VecStrideSum(Vec v, PetscInt start, PetscScalar *sum)
    327: {
    328:   PetscInt           i, n, bs;
    329:   const PetscScalar *x;
    330:   PetscScalar        local_sum = 0.0;

    332:   PetscFunctionBegin;
    335:   PetscAssertPointer(sum, 3);
    336:   PetscCall(VecGetLocalSize(v, &n));
    337:   PetscCall(VecGetBlockSize(v, &bs));
    338:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    339:   PetscCheck(start < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start, bs);
    340:   PetscCall(VecGetArrayRead(v, &x));
    341:   for (i = start; i < n; i += bs) local_sum += x[i];
    342:   PetscCallMPI(MPIU_Allreduce(&local_sum, sum, 1, MPIU_SCALAR, MPIU_SUM, PetscObjectComm((PetscObject)v)));
    343:   PetscCall(VecRestoreArrayRead(v, &x));
    344:   PetscFunctionReturn(PETSC_SUCCESS);
    345: }

    347: /*@
    348:   VecStrideScaleAll - Scales the subvectors of a vector defined
    349:   by a starting point and a stride.

    351:   Logically Collective

    353:   Input Parameters:
    354: + v      - the vector
    355: - scales - values to multiply each subvector entry by

    357:   Level: advanced

    359:   Notes:
    360:   One must call `VecSetBlockSize()` before this routine to set the stride
    361:   information, or use a vector created from a multicomponent `DMDA`.

    363:   The dimension of scales must be the same as the vector block size

    365: .seealso: `Vec`, `VecNorm()`, `VecStrideScale()`, `VecScale()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
    366: @*/
    367: PetscErrorCode VecStrideScaleAll(Vec v, const PetscScalar *scales)
    368: {
    369:   PetscInt     i, j, n, bs;
    370:   PetscScalar *x;

    372:   PetscFunctionBegin;
    374:   PetscAssertPointer(scales, 2);
    375:   PetscCall(VecGetLocalSize(v, &n));
    376:   PetscCall(VecGetBlockSize(v, &bs));
    377:   PetscCall(VecGetArray(v, &x));
    378:   /* need to provide optimized code for each bs */
    379:   for (i = 0; i < n; i += bs) {
    380:     for (j = 0; j < bs; j++) x[i + j] *= scales[j];
    381:   }
    382:   PetscCall(VecRestoreArray(v, &x));
    383:   PetscFunctionReturn(PETSC_SUCCESS);
    384: }

    386: /*@
    387:   VecStrideNormAll - Computes the norms of subvectors of a vector defined
    388:   by a starting point and a stride.

    390:   Collective

    392:   Input Parameters:
    393: + v     - the vector
    394: - ntype - type of norm, one of `NORM_1`, `NORM_2`, `NORM_INFINITY`

    396:   Output Parameter:
    397: . nrm - the norms

    399:   Level: advanced

    401:   Notes:
    402:   One must call `VecSetBlockSize()` before this routine to set the stride
    403:   information, or use a vector created from a multicomponent `DMDA`.

    405:   If x is the array representing the vector x then this computes the norm
    406:   of the array (x[start],x[start+stride],x[start+2*stride], ....) for each start < stride

    408:   The dimension of nrm must be the same as the vector block size

    410:   This will only work if the desire subvector is a stride subvector

    412: .seealso: `Vec`, `VecNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
    413: @*/
    414: PetscErrorCode VecStrideNormAll(Vec v, NormType ntype, PetscReal nrm[])
    415: {
    416:   PetscInt           i, j, n, bs;
    417:   const PetscScalar *x;
    418:   PetscReal          tnorm[128];
    419:   MPI_Comm           comm;

    421:   PetscFunctionBegin;
    424:   PetscAssertPointer(nrm, 3);
    425:   PetscCall(VecGetLocalSize(v, &n));
    426:   PetscCall(VecGetArrayRead(v, &x));
    427:   PetscCall(PetscObjectGetComm((PetscObject)v, &comm));

    429:   PetscCall(VecGetBlockSize(v, &bs));
    430:   PetscCheck(bs <= 128, comm, PETSC_ERR_SUP, "Currently supports only blocksize up to 128");

    432:   if (ntype == NORM_2) {
    433:     PetscScalar sum[128];
    434:     for (j = 0; j < bs; j++) sum[j] = 0.0;
    435:     for (i = 0; i < n; i += bs) {
    436:       for (j = 0; j < bs; j++) sum[j] += x[i + j] * (PetscConj(x[i + j]));
    437:     }
    438:     for (j = 0; j < bs; j++) tnorm[j] = PetscRealPart(sum[j]);

    440:     PetscCallMPI(MPIU_Allreduce(tnorm, nrm, (PetscMPIInt)bs, MPIU_REAL, MPIU_SUM, comm));
    441:     for (j = 0; j < bs; j++) nrm[j] = PetscSqrtReal(nrm[j]);
    442:   } else if (ntype == NORM_1) {
    443:     for (j = 0; j < bs; j++) tnorm[j] = 0.0;

    445:     for (i = 0; i < n; i += bs) {
    446:       for (j = 0; j < bs; j++) tnorm[j] += PetscAbsScalar(x[i + j]);
    447:     }

    449:     PetscCallMPI(MPIU_Allreduce(tnorm, nrm, (PetscMPIInt)bs, MPIU_REAL, MPIU_SUM, comm));
    450:   } else if (ntype == NORM_INFINITY) {
    451:     PetscReal tmp;
    452:     for (j = 0; j < bs; j++) tnorm[j] = 0.0;

    454:     for (i = 0; i < n; i += bs) {
    455:       for (j = 0; j < bs; j++) {
    456:         if ((tmp = PetscAbsScalar(x[i + j])) > tnorm[j]) tnorm[j] = tmp;
    457:         /* check special case of tmp == NaN */
    458:         if (tmp != tmp) {
    459:           tnorm[j] = tmp;
    460:           break;
    461:         }
    462:       }
    463:     }
    464:     PetscCallMPI(MPIU_Allreduce(tnorm, nrm, (PetscMPIInt)bs, MPIU_REAL, MPIU_MAX, comm));
    465:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");
    466:   PetscCall(VecRestoreArrayRead(v, &x));
    467:   PetscFunctionReturn(PETSC_SUCCESS);
    468: }

    470: /*@
    471:   VecStrideMaxAll - Computes the maximums of subvectors of a vector defined
    472:   by a starting point and a stride and optionally its location.

    474:   Collective

    476:   Input Parameter:
    477: . v - the vector

    479:   Output Parameters:
    480: + idex - the location where the maximum occurred (not supported, pass `NULL`,
    481:            if you need this, send mail to petsc-maint@mcs.anl.gov to request it)
    482: - nrm  - the maximum values of each subvector

    484:   Level: advanced

    486:   Notes:
    487:   One must call `VecSetBlockSize()` before this routine to set the stride
    488:   information, or use a vector created from a multicomponent `DMDA`.

    490:   The dimension of nrm must be the same as the vector block size

    492: .seealso: `Vec`, `VecMax()`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`
    493: @*/
    494: PetscErrorCode VecStrideMaxAll(Vec v, PetscInt idex[], PetscReal nrm[])
    495: {
    496:   PetscInt           i, j, n, bs;
    497:   const PetscScalar *x;
    498:   PetscReal          max[128], tmp;
    499:   MPI_Comm           comm;

    501:   PetscFunctionBegin;
    503:   PetscAssertPointer(nrm, 3);
    504:   PetscCheck(!idex, PETSC_COMM_SELF, PETSC_ERR_SUP, "No support yet for returning index; send mail to petsc-maint@mcs.anl.gov asking for it");
    505:   PetscCall(VecGetLocalSize(v, &n));
    506:   PetscCall(VecGetArrayRead(v, &x));
    507:   PetscCall(PetscObjectGetComm((PetscObject)v, &comm));

    509:   PetscCall(VecGetBlockSize(v, &bs));
    510:   PetscCheck(bs <= 128, comm, PETSC_ERR_SUP, "Currently supports only blocksize up to 128");

    512:   if (!n) {
    513:     for (j = 0; j < bs; j++) max[j] = PETSC_MIN_REAL;
    514:   } else {
    515:     for (j = 0; j < bs; j++) max[j] = PetscRealPart(x[j]);

    517:     for (i = bs; i < n; i += bs) {
    518:       for (j = 0; j < bs; j++) {
    519:         if ((tmp = PetscRealPart(x[i + j])) > max[j]) max[j] = tmp;
    520:       }
    521:     }
    522:   }
    523:   PetscCallMPI(MPIU_Allreduce(max, nrm, (PetscMPIInt)bs, MPIU_REAL, MPIU_MAX, comm));

    525:   PetscCall(VecRestoreArrayRead(v, &x));
    526:   PetscFunctionReturn(PETSC_SUCCESS);
    527: }

    529: /*@
    530:   VecStrideMinAll - Computes the minimum of subvector of a vector defined
    531:   by a starting point and a stride and optionally its location.

    533:   Collective

    535:   Input Parameter:
    536: . v - the vector

    538:   Output Parameters:
    539: + idex - the location where the minimum occurred (not supported, pass `NULL`,
    540:            if you need this, send mail to petsc-maint@mcs.anl.gov to request it)
    541: - nrm  - the minimums of each subvector

    543:   Level: advanced

    545:   Notes:
    546:   One must call `VecSetBlockSize()` before this routine to set the stride
    547:   information, or use a vector created from a multicomponent `DMDA`.

    549:   The dimension of `nrm` must be the same as the vector block size

    551: .seealso: `Vec`, `VecMin()`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMax()`
    552: @*/
    553: PetscErrorCode VecStrideMinAll(Vec v, PetscInt idex[], PetscReal nrm[])
    554: {
    555:   PetscInt           i, n, bs, j;
    556:   const PetscScalar *x;
    557:   PetscReal          min[128], tmp;
    558:   MPI_Comm           comm;

    560:   PetscFunctionBegin;
    562:   PetscAssertPointer(nrm, 3);
    563:   PetscCheck(!idex, PETSC_COMM_SELF, PETSC_ERR_SUP, "No support yet for returning index; send mail to petsc-maint@mcs.anl.gov asking for it");
    564:   PetscCall(VecGetLocalSize(v, &n));
    565:   PetscCall(VecGetArrayRead(v, &x));
    566:   PetscCall(PetscObjectGetComm((PetscObject)v, &comm));

    568:   PetscCall(VecGetBlockSize(v, &bs));
    569:   PetscCheck(bs <= 128, comm, PETSC_ERR_SUP, "Currently supports only blocksize up to 128");

    571:   if (!n) {
    572:     for (j = 0; j < bs; j++) min[j] = PETSC_MAX_REAL;
    573:   } else {
    574:     for (j = 0; j < bs; j++) min[j] = PetscRealPart(x[j]);

    576:     for (i = bs; i < n; i += bs) {
    577:       for (j = 0; j < bs; j++) {
    578:         if ((tmp = PetscRealPart(x[i + j])) < min[j]) min[j] = tmp;
    579:       }
    580:     }
    581:   }
    582:   PetscCallMPI(MPIU_Allreduce(min, nrm, (PetscMPIInt)bs, MPIU_REAL, MPIU_MIN, comm));

    584:   PetscCall(VecRestoreArrayRead(v, &x));
    585:   PetscFunctionReturn(PETSC_SUCCESS);
    586: }

    588: /*@
    589:   VecStrideSumAll - Computes the sums of subvectors of a vector defined by a stride.

    591:   Collective

    593:   Input Parameter:
    594: . v - the vector

    596:   Output Parameter:
    597: . sums - the sums

    599:   Level: advanced

    601:   Notes:
    602:   One must call `VecSetBlockSize()` before this routine to set the stride
    603:   information, or use a vector created from a multicomponent `DMDA`.

    605:   If x is the array representing the vector x then this computes the sum
    606:   of the array (x[start],x[start+stride],x[start+2*stride], ....) for each start < stride

    608: .seealso: `Vec`, `VecSum()`, `VecStrideGather()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`
    609: @*/
    610: PetscErrorCode VecStrideSumAll(Vec v, PetscScalar sums[])
    611: {
    612:   PetscInt           i, j, n, bs;
    613:   const PetscScalar *x;
    614:   PetscScalar        local_sums[128];
    615:   MPI_Comm           comm;

    617:   PetscFunctionBegin;
    619:   PetscAssertPointer(sums, 2);
    620:   PetscCall(VecGetLocalSize(v, &n));
    621:   PetscCall(VecGetArrayRead(v, &x));
    622:   PetscCall(PetscObjectGetComm((PetscObject)v, &comm));

    624:   PetscCall(VecGetBlockSize(v, &bs));
    625:   PetscCheck(bs <= 128, comm, PETSC_ERR_SUP, "Currently supports only blocksize up to 128");

    627:   for (j = 0; j < bs; j++) local_sums[j] = 0.0;
    628:   for (i = 0; i < n; i += bs) {
    629:     for (j = 0; j < bs; j++) local_sums[j] += x[i + j];
    630:   }
    631:   PetscCallMPI(MPIU_Allreduce(local_sums, sums, (PetscMPIInt)bs, MPIU_SCALAR, MPIU_SUM, comm));

    633:   PetscCall(VecRestoreArrayRead(v, &x));
    634:   PetscFunctionReturn(PETSC_SUCCESS);
    635: }

    637: /*----------------------------------------------------------------------------------------------*/
    638: /*@
    639:   VecStrideGatherAll - Gathers all the single components from a multi-component vector into
    640:   separate vectors.

    642:   Collective

    644:   Input Parameters:
    645: + v    - the vector
    646: - addv - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    648:   Output Parameter:
    649: . s - the location where the subvectors are stored

    651:   Level: advanced

    653:   Notes:
    654:   One must call `VecSetBlockSize()` before this routine to set the stride
    655:   information, or use a vector created from a multicomponent `DMDA`.

    657:   If x is the array representing the vector x then this gathers
    658:   the arrays (x[start],x[start+stride],x[start+2*stride], ....)
    659:   for start=0,1,2,...bs-1

    661:   The parallel layout of the vector and the subvector must be the same;
    662:   i.e., nlocal of v = stride*(nlocal of s)

    664:   Not optimized; could be easily

    666: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGather()`,
    667:           `VecStrideScatterAll()`
    668: @*/
    669: PetscErrorCode VecStrideGatherAll(Vec v, Vec s[], InsertMode addv)
    670: {
    671:   PetscInt           i, n, n2, bs, j, k, *bss = NULL, nv, jj, nvc;
    672:   PetscScalar      **y;
    673:   const PetscScalar *x;

    675:   PetscFunctionBegin;
    677:   PetscAssertPointer(s, 2);
    679:   PetscCall(VecGetLocalSize(v, &n));
    680:   PetscCall(VecGetLocalSize(s[0], &n2));
    681:   PetscCall(VecGetArrayRead(v, &x));
    682:   PetscCall(VecGetBlockSize(v, &bs));
    683:   PetscCheck(bs > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Input vector does not have a valid blocksize set");

    685:   PetscCall(PetscMalloc2(bs, &y, bs, &bss));
    686:   nv  = 0;
    687:   nvc = 0;
    688:   for (i = 0; i < bs; i++) {
    689:     PetscCall(VecGetBlockSize(s[i], &bss[i]));
    690:     if (bss[i] < 1) bss[i] = 1; /* if user never set it then assume 1  Re: [PETSC #8241] VecStrideGatherAll */
    691:     PetscCall(VecGetArray(s[i], &y[i]));
    692:     nvc += bss[i];
    693:     nv++;
    694:     PetscCheck(nvc <= bs, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Number of subvectors in subvectors > number of vectors in main vector");
    695:     if (nvc == bs) break;
    696:   }

    698:   n = n / bs;

    700:   jj = 0;
    701:   if (addv == INSERT_VALUES) {
    702:     for (j = 0; j < nv; j++) {
    703:       for (k = 0; k < bss[j]; k++) {
    704:         for (i = 0; i < n; i++) y[j][i * bss[j] + k] = x[bs * i + jj + k];
    705:       }
    706:       jj += bss[j];
    707:     }
    708:   } else if (addv == ADD_VALUES) {
    709:     for (j = 0; j < nv; j++) {
    710:       for (k = 0; k < bss[j]; k++) {
    711:         for (i = 0; i < n; i++) y[j][i * bss[j] + k] += x[bs * i + jj + k];
    712:       }
    713:       jj += bss[j];
    714:     }
    715: #if !defined(PETSC_USE_COMPLEX)
    716:   } else if (addv == MAX_VALUES) {
    717:     for (j = 0; j < nv; j++) {
    718:       for (k = 0; k < bss[j]; k++) {
    719:         for (i = 0; i < n; i++) y[j][i * bss[j] + k] = PetscMax(y[j][i * bss[j] + k], x[bs * i + jj + k]);
    720:       }
    721:       jj += bss[j];
    722:     }
    723: #endif
    724:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    726:   PetscCall(VecRestoreArrayRead(v, &x));
    727:   for (i = 0; i < nv; i++) PetscCall(VecRestoreArray(s[i], &y[i]));

    729:   PetscCall(PetscFree2(y, bss));
    730:   PetscFunctionReturn(PETSC_SUCCESS);
    731: }

    733: /*@
    734:   VecStrideScatterAll - Scatters all the single components from separate vectors into
    735:   a multi-component vector.

    737:   Collective

    739:   Input Parameters:
    740: + s    - the location where the subvectors are stored
    741: - addv - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    743:   Output Parameter:
    744: . v - the multicomponent vector

    746:   Level: advanced

    748:   Notes:
    749:   One must call `VecSetBlockSize()` before this routine to set the stride
    750:   information, or use a vector created from a multicomponent `DMDA`.

    752:   The parallel layout of the vector and the subvector must be the same;
    753:   i.e., nlocal of v = stride*(nlocal of s)

    755:   Not optimized; could be easily

    757: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGather()`,

    759: @*/
    760: PetscErrorCode VecStrideScatterAll(Vec s[], Vec v, InsertMode addv)
    761: {
    762:   PetscInt            i, n, n2, bs, j, jj, k, *bss = NULL, nv, nvc;
    763:   PetscScalar        *x;
    764:   PetscScalar const **y;

    766:   PetscFunctionBegin;
    768:   PetscAssertPointer(s, 1);
    770:   PetscCall(VecGetLocalSize(v, &n));
    771:   PetscCall(VecGetLocalSize(s[0], &n2));
    772:   PetscCall(VecGetArray(v, &x));
    773:   PetscCall(VecGetBlockSize(v, &bs));
    774:   PetscCheck(bs > 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Input vector does not have a valid blocksize set");

    776:   PetscCall(PetscMalloc2(bs, (PetscScalar ***)&y, bs, &bss));
    777:   nv  = 0;
    778:   nvc = 0;
    779:   for (i = 0; i < bs; i++) {
    780:     PetscCall(VecGetBlockSize(s[i], &bss[i]));
    781:     if (bss[i] < 1) bss[i] = 1; /* if user never set it then assume 1  Re: [PETSC #8241] VecStrideGatherAll */
    782:     PetscCall(VecGetArrayRead(s[i], &y[i]));
    783:     nvc += bss[i];
    784:     nv++;
    785:     PetscCheck(nvc <= bs, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Number of subvectors in subvectors > number of vectors in main vector");
    786:     if (nvc == bs) break;
    787:   }

    789:   n = n / bs;

    791:   jj = 0;
    792:   if (addv == INSERT_VALUES) {
    793:     for (j = 0; j < nv; j++) {
    794:       for (k = 0; k < bss[j]; k++) {
    795:         for (i = 0; i < n; i++) x[bs * i + jj + k] = y[j][i * bss[j] + k];
    796:       }
    797:       jj += bss[j];
    798:     }
    799:   } else if (addv == ADD_VALUES) {
    800:     for (j = 0; j < nv; j++) {
    801:       for (k = 0; k < bss[j]; k++) {
    802:         for (i = 0; i < n; i++) x[bs * i + jj + k] += y[j][i * bss[j] + k];
    803:       }
    804:       jj += bss[j];
    805:     }
    806: #if !defined(PETSC_USE_COMPLEX)
    807:   } else if (addv == MAX_VALUES) {
    808:     for (j = 0; j < nv; j++) {
    809:       for (k = 0; k < bss[j]; k++) {
    810:         for (i = 0; i < n; i++) x[bs * i + jj + k] = PetscMax(x[bs * i + jj + k], y[j][i * bss[j] + k]);
    811:       }
    812:       jj += bss[j];
    813:     }
    814: #endif
    815:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    817:   PetscCall(VecRestoreArray(v, &x));
    818:   for (i = 0; i < nv; i++) PetscCall(VecRestoreArrayRead(s[i], &y[i]));
    819:   PetscCall(PetscFree2(*(PetscScalar ***)&y, bss));
    820:   PetscFunctionReturn(PETSC_SUCCESS);
    821: }

    823: /*@
    824:   VecStrideGather - Gathers a single component from a multi-component vector into
    825:   another vector.

    827:   Collective

    829:   Input Parameters:
    830: + v     - the vector
    831: . start - starting point of the subvector (defined by a stride)
    832: - addv  - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    834:   Output Parameter:
    835: . s - the location where the subvector is stored

    837:   Level: advanced

    839:   Notes:
    840:   One must call `VecSetBlockSize()` before this routine to set the stride
    841:   information, or use a vector created from a multicomponent `DMDA`.

    843:   If x is the array representing the vector x then this gathers
    844:   the array (x[start],x[start+stride],x[start+2*stride], ....)

    846:   The parallel layout of the vector and the subvector must be the same;
    847:   i.e., nlocal of v = stride*(nlocal of s)

    849:   Not optimized; could be easily

    851: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideScatter()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGatherAll()`,
    852:           `VecStrideScatterAll()`
    853: @*/
    854: PetscErrorCode VecStrideGather(Vec v, PetscInt start, Vec s, InsertMode addv)
    855: {
    856:   PetscFunctionBegin;
    860:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    861:   PetscCheck(start < v->map->bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start,
    862:              v->map->bs);
    863:   PetscUseTypeMethod(v, stridegather, start, s, addv);
    864:   PetscFunctionReturn(PETSC_SUCCESS);
    865: }

    867: /*@
    868:   VecStrideScatter - Scatters a single component from a vector into a multi-component vector.

    870:   Collective

    872:   Input Parameters:
    873: + s     - the single-component vector
    874: . start - starting point of the subvector (defined by a stride)
    875: - addv  - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    877:   Output Parameter:
    878: . v - the location where the subvector is scattered (the multi-component vector)

    880:   Level: advanced

    882:   Notes:
    883:   One must call `VecSetBlockSize()` on the multi-component vector before this
    884:   routine to set the stride  information, or use a vector created from a multicomponent `DMDA`.

    886:   The parallel layout of the vector and the subvector must be the same;
    887:   i.e., nlocal of v = stride*(nlocal of s)

    889:   Not optimized; could be easily

    891: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGatherAll()`,
    892:           `VecStrideScatterAll()`, `VecStrideSubSetScatter()`, `VecStrideSubSetGather()`
    893: @*/
    894: PetscErrorCode VecStrideScatter(Vec s, PetscInt start, Vec v, InsertMode addv)
    895: {
    896:   PetscFunctionBegin;
    900:   PetscCheck(start >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Negative start %" PetscInt_FMT, start);
    901:   PetscCheck(start < v->map->bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Start of stride subvector (%" PetscInt_FMT ") is too large for stride. Have you set the vector blocksize (%" PetscInt_FMT ") correctly with VecSetBlockSize()?", start,
    902:              v->map->bs);
    903:   PetscCall((*v->ops->stridescatter)(s, start, v, addv));
    904:   PetscFunctionReturn(PETSC_SUCCESS);
    905: }

    907: /*@
    908:   VecStrideSubSetGather - Gathers a subset of components from a multi-component vector into
    909:   another vector.

    911:   Collective

    913:   Input Parameters:
    914: + v    - the vector
    915: . nidx - the number of indices
    916: . idxv - the indices of the components 0 <= idxv[0] ...idxv[nidx-1] < bs(v), they need not be sorted
    917: . idxs - the indices of the components 0 <= idxs[0] ...idxs[nidx-1] < bs(s), they need not be sorted, may be null if nidx == bs(s) or is `PETSC_DETERMINE`
    918: - addv - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    920:   Output Parameter:
    921: . s - the location where the subvector is stored

    923:   Level: advanced

    925:   Notes:
    926:   One must call `VecSetBlockSize()` on both vectors before this routine to set the stride
    927:   information, or use a vector created from a multicomponent `DMDA`.

    929:   The parallel layout of the vector and the subvector must be the same;

    931:   Not optimized; could be easily

    933: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideScatter()`, `VecStrideGather()`, `VecStrideSubSetScatter()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGatherAll()`,
    934:           `VecStrideScatterAll()`
    935: @*/
    936: PetscErrorCode VecStrideSubSetGather(Vec v, PetscInt nidx, const PetscInt idxv[], const PetscInt idxs[], Vec s, InsertMode addv)
    937: {
    938:   PetscFunctionBegin;
    941:   if (nidx == PETSC_DETERMINE) nidx = s->map->bs;
    942:   PetscUseTypeMethod(v, stridesubsetgather, nidx, idxv, idxs, s, addv);
    943:   PetscFunctionReturn(PETSC_SUCCESS);
    944: }

    946: /*@
    947:   VecStrideSubSetScatter - Scatters components from a vector into a subset of components of a multi-component vector.

    949:   Collective

    951:   Input Parameters:
    952: + s    - the smaller-component vector
    953: . nidx - the number of indices in idx
    954: . idxs - the indices of the components in the smaller-component vector, 0 <= idxs[0] ...idxs[nidx-1] < bs(s) they need not be sorted, may be null if nidx == bs(s) or is `PETSC_DETERMINE`
    955: . idxv - the indices of the components in the larger-component vector, 0 <= idx[0] ...idx[nidx-1] < bs(v) they need not be sorted
    956: - addv - one of `ADD_VALUES`, `INSERT_VALUES`, `MAX_VALUES`

    958:   Output Parameter:
    959: . v - the location where the subvector is into scattered (the multi-component vector)

    961:   Level: advanced

    963:   Notes:
    964:   One must call `VecSetBlockSize()` on the vectors before this
    965:   routine to set the stride  information, or use a vector created from a multicomponent `DMDA`.

    967:   The parallel layout of the vector and the subvector must be the same;

    969:   Not optimized; could be easily

    971: .seealso: `Vec`, `VecStrideNorm()`, `VecStrideGather()`, `VecStrideSubSetGather()`, `VecStrideMin()`, `VecStrideMax()`, `VecStrideGatherAll()`,
    972:           `VecStrideScatterAll()`
    973: @*/
    974: PetscErrorCode VecStrideSubSetScatter(Vec s, PetscInt nidx, const PetscInt idxs[], const PetscInt idxv[], Vec v, InsertMode addv)
    975: {
    976:   PetscFunctionBegin;
    979:   if (nidx == PETSC_DETERMINE) nidx = s->map->bs;
    980:   PetscCall((*v->ops->stridesubsetscatter)(s, nidx, idxs, idxv, v, addv));
    981:   PetscFunctionReturn(PETSC_SUCCESS);
    982: }

    984: PetscErrorCode VecStrideGather_Default(Vec v, PetscInt start, Vec s, InsertMode addv)
    985: {
    986:   PetscInt           i, n, bs, ns;
    987:   const PetscScalar *x;
    988:   PetscScalar       *y;

    990:   PetscFunctionBegin;
    991:   PetscCall(VecGetLocalSize(v, &n));
    992:   PetscCall(VecGetLocalSize(s, &ns));
    993:   PetscCall(VecGetArrayRead(v, &x));
    994:   PetscCall(VecGetArray(s, &y));

    996:   bs = v->map->bs;
    997:   PetscCheck(n == ns * bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Subvector length * blocksize %" PetscInt_FMT " not correct for gather from original vector %" PetscInt_FMT, ns * bs, n);
    998:   x += start;
    999:   n = n / bs;

    1001:   if (addv == INSERT_VALUES) {
    1002:     for (i = 0; i < n; i++) y[i] = x[bs * i];
    1003:   } else if (addv == ADD_VALUES) {
    1004:     for (i = 0; i < n; i++) y[i] += x[bs * i];
    1005: #if !defined(PETSC_USE_COMPLEX)
    1006:   } else if (addv == MAX_VALUES) {
    1007:     for (i = 0; i < n; i++) y[i] = PetscMax(y[i], x[bs * i]);
    1008: #endif
    1009:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    1011:   PetscCall(VecRestoreArrayRead(v, &x));
    1012:   PetscCall(VecRestoreArray(s, &y));
    1013:   PetscFunctionReturn(PETSC_SUCCESS);
    1014: }

    1016: PetscErrorCode VecStrideScatter_Default(Vec s, PetscInt start, Vec v, InsertMode addv)
    1017: {
    1018:   PetscInt           i, n, bs, ns;
    1019:   PetscScalar       *x;
    1020:   const PetscScalar *y;

    1022:   PetscFunctionBegin;
    1023:   PetscCall(VecGetLocalSize(v, &n));
    1024:   PetscCall(VecGetLocalSize(s, &ns));
    1025:   PetscCall(VecGetArray(v, &x));
    1026:   PetscCall(VecGetArrayRead(s, &y));

    1028:   bs = v->map->bs;
    1029:   PetscCheck(n == ns * bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Subvector length * blocksize %" PetscInt_FMT " not correct for scatter to multicomponent vector %" PetscInt_FMT, ns * bs, n);
    1030:   x += start;
    1031:   n = n / bs;

    1033:   if (addv == INSERT_VALUES) {
    1034:     for (i = 0; i < n; i++) x[bs * i] = y[i];
    1035:   } else if (addv == ADD_VALUES) {
    1036:     for (i = 0; i < n; i++) x[bs * i] += y[i];
    1037: #if !defined(PETSC_USE_COMPLEX)
    1038:   } else if (addv == MAX_VALUES) {
    1039:     for (i = 0; i < n; i++) x[bs * i] = PetscMax(y[i], x[bs * i]);
    1040: #endif
    1041:   } else SETERRQ(PetscObjectComm((PetscObject)s), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    1043:   PetscCall(VecRestoreArray(v, &x));
    1044:   PetscCall(VecRestoreArrayRead(s, &y));
    1045:   PetscFunctionReturn(PETSC_SUCCESS);
    1046: }

    1048: PetscErrorCode VecStrideSubSetGather_Default(Vec v, PetscInt nidx, const PetscInt idxv[], const PetscInt idxs[], Vec s, InsertMode addv)
    1049: {
    1050:   PetscInt           i, j, n, bs, bss, ns;
    1051:   const PetscScalar *x;
    1052:   PetscScalar       *y;

    1054:   PetscFunctionBegin;
    1055:   PetscCall(VecGetLocalSize(v, &n));
    1056:   PetscCall(VecGetLocalSize(s, &ns));
    1057:   PetscCall(VecGetArrayRead(v, &x));
    1058:   PetscCall(VecGetArray(s, &y));

    1060:   bs  = v->map->bs;
    1061:   bss = s->map->bs;
    1062:   n   = n / bs;

    1064:   if (PetscDefined(USE_DEBUG)) {
    1065:     PetscCheck(n == ns / bss, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Incompatible layout of vectors");
    1066:     for (j = 0; j < nidx; j++) {
    1067:       PetscCheck(idxv[j] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "idx[%" PetscInt_FMT "] %" PetscInt_FMT " is negative", j, idxv[j]);
    1068:       PetscCheck(idxv[j] < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "idx[%" PetscInt_FMT "] %" PetscInt_FMT " is greater than or equal to vector blocksize %" PetscInt_FMT, j, idxv[j], bs);
    1069:     }
    1070:     PetscCheck(idxs || bss == nidx, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must provide idxs when not gathering into all locations");
    1071:   }

    1073:   if (addv == INSERT_VALUES) {
    1074:     if (!idxs) {
    1075:       for (i = 0; i < n; i++) {
    1076:         for (j = 0; j < bss; j++) y[bss * i + j] = x[bs * i + idxv[j]];
    1077:       }
    1078:     } else {
    1079:       for (i = 0; i < n; i++) {
    1080:         for (j = 0; j < bss; j++) y[bss * i + idxs[j]] = x[bs * i + idxv[j]];
    1081:       }
    1082:     }
    1083:   } else if (addv == ADD_VALUES) {
    1084:     if (!idxs) {
    1085:       for (i = 0; i < n; i++) {
    1086:         for (j = 0; j < bss; j++) y[bss * i + j] += x[bs * i + idxv[j]];
    1087:       }
    1088:     } else {
    1089:       for (i = 0; i < n; i++) {
    1090:         for (j = 0; j < bss; j++) y[bss * i + idxs[j]] += x[bs * i + idxv[j]];
    1091:       }
    1092:     }
    1093: #if !defined(PETSC_USE_COMPLEX)
    1094:   } else if (addv == MAX_VALUES) {
    1095:     if (!idxs) {
    1096:       for (i = 0; i < n; i++) {
    1097:         for (j = 0; j < bss; j++) y[bss * i + j] = PetscMax(y[bss * i + j], x[bs * i + idxv[j]]);
    1098:       }
    1099:     } else {
    1100:       for (i = 0; i < n; i++) {
    1101:         for (j = 0; j < bss; j++) y[bss * i + idxs[j]] = PetscMax(y[bss * i + idxs[j]], x[bs * i + idxv[j]]);
    1102:       }
    1103:     }
    1104: #endif
    1105:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    1107:   PetscCall(VecRestoreArrayRead(v, &x));
    1108:   PetscCall(VecRestoreArray(s, &y));
    1109:   PetscFunctionReturn(PETSC_SUCCESS);
    1110: }

    1112: PetscErrorCode VecStrideSubSetScatter_Default(Vec s, PetscInt nidx, const PetscInt idxs[], const PetscInt idxv[], Vec v, InsertMode addv)
    1113: {
    1114:   PetscInt           j, i, n, bs, ns, bss;
    1115:   PetscScalar       *x;
    1116:   const PetscScalar *y;

    1118:   PetscFunctionBegin;
    1119:   PetscCall(VecGetLocalSize(v, &n));
    1120:   PetscCall(VecGetLocalSize(s, &ns));
    1121:   PetscCall(VecGetArray(v, &x));
    1122:   PetscCall(VecGetArrayRead(s, &y));

    1124:   bs  = v->map->bs;
    1125:   bss = s->map->bs;
    1126:   n   = n / bs;

    1128:   if (PetscDefined(USE_DEBUG)) {
    1129:     PetscCheck(n == ns / bss, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Incompatible layout of vectors");
    1130:     for (j = 0; j < bss; j++) {
    1131:       if (idxs) {
    1132:         PetscCheck(idxs[j] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "idx[%" PetscInt_FMT "] %" PetscInt_FMT " is negative", j, idxs[j]);
    1133:         PetscCheck(idxs[j] < bs, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "idx[%" PetscInt_FMT "] %" PetscInt_FMT " is greater than or equal to vector blocksize %" PetscInt_FMT, j, idxs[j], bs);
    1134:       }
    1135:     }
    1136:     PetscCheck(idxs || bss == nidx, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Must provide idxs when not scattering from all locations");
    1137:   }

    1139:   if (addv == INSERT_VALUES) {
    1140:     if (!idxs) {
    1141:       for (i = 0; i < n; i++) {
    1142:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] = y[bss * i + j];
    1143:       }
    1144:     } else {
    1145:       for (i = 0; i < n; i++) {
    1146:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] = y[bss * i + idxs[j]];
    1147:       }
    1148:     }
    1149:   } else if (addv == ADD_VALUES) {
    1150:     if (!idxs) {
    1151:       for (i = 0; i < n; i++) {
    1152:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] += y[bss * i + j];
    1153:       }
    1154:     } else {
    1155:       for (i = 0; i < n; i++) {
    1156:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] += y[bss * i + idxs[j]];
    1157:       }
    1158:     }
    1159: #if !defined(PETSC_USE_COMPLEX)
    1160:   } else if (addv == MAX_VALUES) {
    1161:     if (!idxs) {
    1162:       for (i = 0; i < n; i++) {
    1163:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] = PetscMax(y[bss * i + j], x[bs * i + idxv[j]]);
    1164:       }
    1165:     } else {
    1166:       for (i = 0; i < n; i++) {
    1167:         for (j = 0; j < bss; j++) x[bs * i + idxv[j]] = PetscMax(y[bss * i + idxs[j]], x[bs * i + idxv[j]]);
    1168:       }
    1169:     }
    1170: #endif
    1171:   } else SETERRQ(PetscObjectComm((PetscObject)v), PETSC_ERR_ARG_UNKNOWN_TYPE, "Unknown norm type");

    1173:   PetscCall(VecRestoreArray(v, &x));
    1174:   PetscCall(VecRestoreArrayRead(s, &y));
    1175:   PetscFunctionReturn(PETSC_SUCCESS);
    1176: }

    1178: static PetscErrorCode VecApplyUnary_Private(Vec v, PetscDeviceContext dctx, const char async_name[], PetscErrorCode (*unary_op)(Vec), PetscScalar (*UnaryFunc)(PetscScalar))
    1179: {
    1180:   PetscFunctionBegin;
    1182:   PetscCall(VecSetErrorIfLocked(v, 1));
    1183:   if (dctx) {
    1184:     PetscErrorCode (*unary_op_async)(Vec, PetscDeviceContext);

    1186:     PetscCall(PetscObjectQueryFunction((PetscObject)v, async_name, &unary_op_async));
    1187:     if (unary_op_async) {
    1188:       PetscCall((*unary_op_async)(v, dctx));
    1189:       PetscFunctionReturn(PETSC_SUCCESS);
    1190:     }
    1191:   }
    1192:   if (unary_op) {
    1194:     PetscCall((*unary_op)(v));
    1195:   } else {
    1196:     PetscInt     n;
    1197:     PetscScalar *x;

    1200:     PetscCall(VecGetLocalSize(v, &n));
    1201:     PetscCall(VecGetArray(v, &x));
    1202:     for (PetscInt i = 0; i < n; ++i) x[i] = UnaryFunc(x[i]);
    1203:     PetscCall(VecRestoreArray(v, &x));
    1204:   }
    1205:   PetscFunctionReturn(PETSC_SUCCESS);
    1206: }

    1208: static PetscScalar ScalarReciprocal_Function(PetscScalar x)
    1209: {
    1210:   const PetscScalar zero = 0.0;

    1212:   return x == zero ? zero : ((PetscScalar)1.0) / x;
    1213: }

    1215: PetscErrorCode VecReciprocalAsync_Private(Vec v, PetscDeviceContext dctx)
    1216: {
    1217:   PetscFunctionBegin;
    1218:   PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(Reciprocal), v->ops->reciprocal, ScalarReciprocal_Function));
    1219:   PetscFunctionReturn(PETSC_SUCCESS);
    1220: }

    1222: PetscErrorCode VecReciprocal_Default(Vec v)
    1223: {
    1224:   PetscFunctionBegin;
    1225:   PetscCall(VecApplyUnary_Private(v, NULL, NULL, NULL, ScalarReciprocal_Function));
    1226:   PetscFunctionReturn(PETSC_SUCCESS);
    1227: }

    1229: static PetscScalar ScalarExp_Function(PetscScalar x)
    1230: {
    1231:   return PetscExpScalar(x);
    1232: }

    1234: PetscErrorCode VecExpAsync_Private(Vec v, PetscDeviceContext dctx)
    1235: {
    1236:   PetscFunctionBegin;
    1238:   PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(Exp), v->ops->exp, ScalarExp_Function));
    1239:   PetscFunctionReturn(PETSC_SUCCESS);
    1240: }

    1242: /*@
    1243:   VecExp - Replaces each component of a vector by e^x_i

    1245:   Not Collective

    1247:   Input Parameter:
    1248: . v - The vector

    1250:   Output Parameter:
    1251: . v - The vector of exponents

    1253:   Level: beginner

    1255: .seealso: `Vec`, `VecLog()`, `VecAbs()`, `VecSqrtAbs()`, `VecReciprocal()`

    1257: @*/
    1258: PetscErrorCode VecExp(Vec v)
    1259: {
    1260:   PetscFunctionBegin;
    1261:   PetscCall(VecExpAsync_Private(v, NULL));
    1262:   PetscFunctionReturn(PETSC_SUCCESS);
    1263: }

    1265: static PetscScalar ScalarLog_Function(PetscScalar x)
    1266: {
    1267:   return PetscLogScalar(x);
    1268: }

    1270: PetscErrorCode VecLogAsync_Private(Vec v, PetscDeviceContext dctx)
    1271: {
    1272:   PetscFunctionBegin;
    1274:   PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(Log), v->ops->log, ScalarLog_Function));
    1275:   PetscFunctionReturn(PETSC_SUCCESS);
    1276: }

    1278: /*@
    1279:   VecLog - Replaces each component of a vector by log(x_i), the natural logarithm

    1281:   Not Collective

    1283:   Input Parameter:
    1284: . v - The vector

    1286:   Output Parameter:
    1287: . v - The vector of logs

    1289:   Level: beginner

    1291: .seealso: `Vec`, `VecExp()`, `VecAbs()`, `VecSqrtAbs()`, `VecReciprocal()`

    1293: @*/
    1294: PetscErrorCode VecLog(Vec v)
    1295: {
    1296:   PetscFunctionBegin;
    1297:   PetscCall(VecLogAsync_Private(v, NULL));
    1298:   PetscFunctionReturn(PETSC_SUCCESS);
    1299: }

    1301: static PetscScalar ScalarAbs_Function(PetscScalar x)
    1302: {
    1303:   return PetscAbsScalar(x);
    1304: }

    1306: PetscErrorCode VecAbsAsync_Private(Vec v, PetscDeviceContext dctx)
    1307: {
    1308:   PetscFunctionBegin;
    1310:   PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(Abs), v->ops->abs, ScalarAbs_Function));
    1311:   PetscFunctionReturn(PETSC_SUCCESS);
    1312: }

    1314: /*@
    1315:   VecAbs - Replaces every element in a vector with its absolute value.

    1317:   Logically Collective

    1319:   Input Parameter:
    1320: . v - the vector

    1322:   Level: intermediate

    1324: .seealso: `Vec`, `VecExp()`, `VecSqrtAbs()`, `VecReciprocal()`, `VecLog()`
    1325: @*/
    1326: PetscErrorCode VecAbs(Vec v)
    1327: {
    1328:   PetscFunctionBegin;
    1329:   PetscCall(VecAbsAsync_Private(v, NULL));
    1330:   PetscFunctionReturn(PETSC_SUCCESS);
    1331: }

    1333: static PetscScalar ScalarConjugate_Function(PetscScalar x)
    1334: {
    1335:   return PetscConj(x);
    1336: }

    1338: PetscErrorCode VecConjugateAsync_Private(Vec v, PetscDeviceContext dctx)
    1339: {
    1340:   PetscFunctionBegin;
    1342:   if (PetscDefined(USE_COMPLEX)) PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(Conjugate), v->ops->conjugate, ScalarConjugate_Function));
    1343:   PetscFunctionReturn(PETSC_SUCCESS);
    1344: }

    1346: /*@
    1347:   VecConjugate - Conjugates a vector. That is, replace every entry in a vector with its complex conjugate

    1349:   Logically Collective

    1351:   Input Parameter:
    1352: . x - the vector

    1354:   Level: intermediate

    1356: .seealso: [](ch_vectors), `Vec`, `VecSet()`
    1357: @*/
    1358: PetscErrorCode VecConjugate(Vec x)
    1359: {
    1360:   PetscFunctionBegin;
    1361:   PetscCall(VecConjugateAsync_Private(x, NULL));
    1362:   PetscFunctionReturn(PETSC_SUCCESS);
    1363: }

    1365: static PetscScalar ScalarSqrtAbs_Function(PetscScalar x)
    1366: {
    1367:   return PetscSqrtScalar(ScalarAbs_Function(x));
    1368: }

    1370: PetscErrorCode VecSqrtAbsAsync_Private(Vec v, PetscDeviceContext dctx)
    1371: {
    1372:   PetscFunctionBegin;
    1374:   PetscCall(VecApplyUnary_Private(v, dctx, VecAsyncFnName(SqrtAbs), v->ops->sqrt, ScalarSqrtAbs_Function));
    1375:   PetscFunctionReturn(PETSC_SUCCESS);
    1376: }

    1378: /*@
    1379:   VecSqrtAbs - Replaces each component of a vector by the square root of its magnitude.

    1381:   Not Collective

    1383:   Input Parameter:
    1384: . v - The vector

    1386:   Level: beginner

    1388:   Note:
    1389:   The actual function is sqrt(|x_i|)

    1391: .seealso: `Vec`, `VecLog()`, `VecExp()`, `VecReciprocal()`, `VecAbs()`

    1393: @*/
    1394: PetscErrorCode VecSqrtAbs(Vec v)
    1395: {
    1396:   PetscFunctionBegin;
    1397:   PetscCall(VecSqrtAbsAsync_Private(v, NULL));
    1398:   PetscFunctionReturn(PETSC_SUCCESS);
    1399: }

    1401: static PetscScalar ScalarImaginaryPart_Function(PetscScalar x)
    1402: {
    1403:   const PetscReal imag = PetscImaginaryPart(x);

    1405: #if PetscDefined(USE_COMPLEX)
    1406:   return PetscCMPLX(imag, 0.0);
    1407: #else
    1408:   return imag;
    1409: #endif
    1410: }

    1412: /*@
    1413:   VecImaginaryPart - Replaces a complex vector with its imginary part

    1415:   Collective

    1417:   Input Parameter:
    1418: . v - the vector

    1420:   Level: beginner

    1422: .seealso: `Vec`, `VecNorm()`, `VecRealPart()`
    1423: @*/
    1424: PetscErrorCode VecImaginaryPart(Vec v)
    1425: {
    1426:   PetscFunctionBegin;
    1428:   PetscCall(VecApplyUnary_Private(v, NULL, NULL, NULL, ScalarImaginaryPart_Function));
    1429:   PetscFunctionReturn(PETSC_SUCCESS);
    1430: }

    1432: static PetscScalar ScalarRealPart_Function(PetscScalar x)
    1433: {
    1434:   const PetscReal real = PetscRealPart(x);

    1436: #if PetscDefined(USE_COMPLEX)
    1437:   return PetscCMPLX(real, 0.0);
    1438: #else
    1439:   return real;
    1440: #endif
    1441: }

    1443: /*@
    1444:   VecRealPart - Replaces a complex vector with its real part

    1446:   Collective

    1448:   Input Parameter:
    1449: . v - the vector

    1451:   Level: beginner

    1453: .seealso: `Vec`, `VecNorm()`, `VecImaginaryPart()`
    1454: @*/
    1455: PetscErrorCode VecRealPart(Vec v)
    1456: {
    1457:   PetscFunctionBegin;
    1459:   PetscCall(VecApplyUnary_Private(v, NULL, NULL, NULL, ScalarRealPart_Function));
    1460:   PetscFunctionReturn(PETSC_SUCCESS);
    1461: }

    1463: /*@
    1464:   VecDotNorm2 - computes the inner product of two vectors and the 2-norm squared of the second vector

    1466:   Collective

    1468:   Input Parameters:
    1469: + s - first vector
    1470: - t - second vector

    1472:   Output Parameters:
    1473: + dp - s'conj(t)
    1474: - nm - t'conj(t)

    1476:   Level: advanced

    1478:   Note:
    1479:   conj(x) is the complex conjugate of x when x is complex

    1481: .seealso: `Vec`, `VecDot()`, `VecNorm()`, `VecDotBegin()`, `VecNormBegin()`, `VecDotEnd()`, `VecNormEnd()`

    1483: @*/
    1484: PetscErrorCode VecDotNorm2(Vec s, Vec t, PetscScalar *dp, PetscReal *nm)
    1485: {
    1486:   PetscScalar work[] = {0.0, 0.0};

    1488:   PetscFunctionBegin;
    1491:   PetscAssertPointer(dp, 3);
    1492:   PetscAssertPointer(nm, 4);
    1495:   PetscCheckSameTypeAndComm(s, 1, t, 2);
    1496:   PetscCheck(s->map->N == t->map->N, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Incompatible vector global lengths");
    1497:   PetscCheck(s->map->n == t->map->n, PETSC_COMM_SELF, PETSC_ERR_ARG_INCOMP, "Incompatible vector local lengths");

    1499:   PetscCall(PetscLogEventBegin(VEC_DotNorm2, s, t, 0, 0));
    1500:   if (s->ops->dotnorm2) {
    1501:     PetscUseTypeMethod(s, dotnorm2, t, work, work + 1);
    1502:   } else {
    1503:     const PetscScalar *sx, *tx;
    1504:     PetscInt           n;

    1506:     PetscCall(VecGetLocalSize(s, &n));
    1507:     PetscCall(VecGetArrayRead(s, &sx));
    1508:     PetscCall(VecGetArrayRead(t, &tx));
    1509:     for (PetscInt i = 0; i < n; ++i) {
    1510:       const PetscScalar txconj = PetscConj(tx[i]);

    1512:       work[0] += sx[i] * txconj;
    1513:       work[1] += tx[i] * txconj;
    1514:     }
    1515:     PetscCall(VecRestoreArrayRead(t, &tx));
    1516:     PetscCall(VecRestoreArrayRead(s, &sx));
    1517:     PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, work, 2, MPIU_SCALAR, MPIU_SUM, PetscObjectComm((PetscObject)s)));
    1518:     PetscCall(PetscLogFlops(4.0 * n));
    1519:   }
    1520:   PetscCall(PetscLogEventEnd(VEC_DotNorm2, s, t, 0, 0));
    1521:   *dp = work[0];
    1522:   *nm = PetscRealPart(work[1]);
    1523:   PetscFunctionReturn(PETSC_SUCCESS);
    1524: }

    1526: /*@
    1527:   VecSum - Computes the sum of all the components of a vector.

    1529:   Collective

    1531:   Input Parameter:
    1532: . v - the vector

    1534:   Output Parameter:
    1535: . sum - the result

    1537:   Level: beginner

    1539: .seealso: `Vec`, `VecMean()`, `VecNorm()`
    1540: @*/
    1541: PetscErrorCode VecSum(Vec v, PetscScalar *sum)
    1542: {
    1543:   PetscScalar tmp = 0.0;

    1545:   PetscFunctionBegin;
    1547:   PetscAssertPointer(sum, 2);
    1548:   if (v->ops->sum) {
    1549:     PetscUseTypeMethod(v, sum, &tmp);
    1550:   } else {
    1551:     const PetscScalar *x;
    1552:     PetscInt           n;

    1554:     PetscCall(VecGetLocalSize(v, &n));
    1555:     PetscCall(VecGetArrayRead(v, &x));
    1556:     for (PetscInt i = 0; i < n; ++i) tmp += x[i];
    1557:     PetscCall(VecRestoreArrayRead(v, &x));
    1558:   }
    1559:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &tmp, 1, MPIU_SCALAR, MPIU_SUM, PetscObjectComm((PetscObject)v)));
    1560:   *sum = tmp;
    1561:   PetscFunctionReturn(PETSC_SUCCESS);
    1562: }

    1564: /*@
    1565:   VecMean - Computes the arithmetic mean of all the components of a vector.

    1567:   Collective

    1569:   Input Parameter:
    1570: . v - the vector

    1572:   Output Parameter:
    1573: . mean - the result

    1575:   Level: beginner

    1577: .seealso: `Vec`, `VecSum()`, `VecNorm()`
    1578: @*/
    1579: PetscErrorCode VecMean(Vec v, PetscScalar *mean)
    1580: {
    1581:   PetscInt n;

    1583:   PetscFunctionBegin;
    1585:   PetscAssertPointer(mean, 2);
    1586:   PetscCall(VecGetSize(v, &n));
    1587:   PetscCall(VecSum(v, mean));
    1588:   *mean /= n;
    1589:   PetscFunctionReturn(PETSC_SUCCESS);
    1590: }

    1592: PetscErrorCode VecShiftAsync_Private(Vec v, PetscScalar shift, PetscDeviceContext dctx)
    1593: {
    1594:   PetscErrorCode (*shift_async)(Vec, PetscScalar, PetscDeviceContext) = NULL;

    1596:   PetscFunctionBegin;
    1597:   if (dctx) {
    1598:     PetscErrorCode (*shift_async)(Vec, PetscScalar, PetscDeviceContext);

    1600:     PetscCall(PetscObjectQueryFunction((PetscObject)v, VecAsyncFnName(Shift), &shift_async));
    1601:   }
    1602:   if (shift_async) {
    1603:     PetscCall((*shift_async)(v, shift, dctx));
    1604:   } else if (v->ops->shift) {
    1605:     PetscUseTypeMethod(v, shift, shift);
    1606:   } else {
    1607:     PetscInt     n;
    1608:     PetscScalar *x;

    1610:     PetscCall(VecGetLocalSize(v, &n));
    1611:     PetscCall(VecGetArray(v, &x));
    1612:     for (PetscInt i = 0; i < n; ++i) x[i] += shift;
    1613:     PetscCall(VecRestoreArray(v, &x));
    1614:     PetscCall(PetscLogFlops(n));
    1615:   }
    1616:   PetscFunctionReturn(PETSC_SUCCESS);
    1617: }

    1619: /*@
    1620:   VecShift - Shifts all of the components of a vector by computing
    1621:   `x[i] = x[i] + shift`.

    1623:   Logically Collective

    1625:   Input Parameters:
    1626: + v     - the vector
    1627: - shift - the shift

    1629:   Level: intermediate

    1631: .seealso: `Vec`, `VecISShift()`
    1632: @*/
    1633: PetscErrorCode VecShift(Vec v, PetscScalar shift)
    1634: {
    1635:   PetscFunctionBegin;
    1638:   PetscCall(VecSetErrorIfLocked(v, 1));
    1639:   if (shift == (PetscScalar)0.0) PetscFunctionReturn(PETSC_SUCCESS);
    1640:   PetscCall(PetscLogEventBegin(VEC_Shift, v, 0, 0, 0));
    1641:   PetscCall(VecShiftAsync_Private(v, shift, NULL));
    1642:   PetscCall(PetscLogEventEnd(VEC_Shift, v, 0, 0, 0));
    1643:   PetscFunctionReturn(PETSC_SUCCESS);
    1644: }

    1646: /*@
    1647:   VecPermute - Permutes a vector in place using the given ordering.

    1649:   Input Parameters:
    1650: + x   - The vector
    1651: . row - The ordering
    1652: - inv - The flag for inverting the permutation

    1654:   Level: beginner

    1656:   Note:
    1657:   This function does not yet support parallel Index Sets with non-local permutations

    1659: .seealso: `Vec`, `MatPermute()`
    1660: @*/
    1661: PetscErrorCode VecPermute(Vec x, IS row, PetscBool inv)
    1662: {
    1663:   PetscScalar    *array, *newArray;
    1664:   const PetscInt *idx;
    1665:   PetscInt        i, rstart, rend;

    1667:   PetscFunctionBegin;
    1670:   PetscCall(VecSetErrorIfLocked(x, 1));
    1671:   PetscCall(VecGetOwnershipRange(x, &rstart, &rend));
    1672:   PetscCall(ISGetIndices(row, &idx));
    1673:   PetscCall(VecGetArray(x, &array));
    1674:   PetscCall(PetscMalloc1(x->map->n, &newArray));
    1675:   PetscCall(PetscArraycpy(newArray, array, x->map->n));
    1676:   if (PetscDefined(USE_DEBUG)) {
    1677:     for (i = 0; i < x->map->n; i++) PetscCheck(!(idx[i] < rstart) && !(idx[i] >= rend), PETSC_COMM_SELF, PETSC_ERR_ARG_CORRUPT, "Permutation index %" PetscInt_FMT " is out of bounds: %" PetscInt_FMT, i, idx[i]);
    1678:   }
    1679:   if (!inv) {
    1680:     for (i = 0; i < x->map->n; i++) array[i] = newArray[idx[i] - rstart];
    1681:   } else {
    1682:     for (i = 0; i < x->map->n; i++) array[idx[i] - rstart] = newArray[i];
    1683:   }
    1684:   PetscCall(VecRestoreArray(x, &array));
    1685:   PetscCall(ISRestoreIndices(row, &idx));
    1686:   PetscCall(PetscFree(newArray));
    1687:   PetscFunctionReturn(PETSC_SUCCESS);
    1688: }

    1690: /*@
    1691:   VecEqual - Compares two vectors. Returns true if the two vectors are either pointing to the same memory buffer,
    1692:   or if the two vectors have the same local and global layout as well as bitwise equality of all entries.
    1693:   Does NOT take round-off errors into account.

    1695:   Collective

    1697:   Input Parameters:
    1698: + vec1 - the first vector
    1699: - vec2 - the second vector

    1701:   Output Parameter:
    1702: . flg - `PETSC_TRUE` if the vectors are equal; `PETSC_FALSE` otherwise.

    1704:   Level: intermediate

    1706: .seealso: `Vec`
    1707: @*/
    1708: PetscErrorCode VecEqual(Vec vec1, Vec vec2, PetscBool *flg)
    1709: {
    1710:   const PetscScalar *v1, *v2;
    1711:   PetscInt           n1, n2, N1, N2;
    1712:   PetscBool          flg1;

    1714:   PetscFunctionBegin;
    1717:   PetscAssertPointer(flg, 3);
    1718:   if (vec1 == vec2) *flg = PETSC_TRUE;
    1719:   else {
    1720:     PetscCall(VecGetSize(vec1, &N1));
    1721:     PetscCall(VecGetSize(vec2, &N2));
    1722:     if (N1 != N2) flg1 = PETSC_FALSE;
    1723:     else {
    1724:       PetscCall(VecGetLocalSize(vec1, &n1));
    1725:       PetscCall(VecGetLocalSize(vec2, &n2));
    1726:       if (n1 != n2) flg1 = PETSC_FALSE;
    1727:       else {
    1728:         PetscCall(VecGetArrayRead(vec1, &v1));
    1729:         PetscCall(VecGetArrayRead(vec2, &v2));
    1730:         PetscCall(PetscArraycmp(v1, v2, n1, &flg1));
    1731:         PetscCall(VecRestoreArrayRead(vec1, &v1));
    1732:         PetscCall(VecRestoreArrayRead(vec2, &v2));
    1733:       }
    1734:     }
    1735:     /* combine results from all processors */
    1736:     PetscCallMPI(MPIU_Allreduce(&flg1, flg, 1, MPIU_BOOL, MPI_MIN, PetscObjectComm((PetscObject)vec1)));
    1737:   }
    1738:   PetscFunctionReturn(PETSC_SUCCESS);
    1739: }

    1741: /*@
    1742:   VecUniqueEntries - Compute the number of unique entries, and those entries

    1744:   Collective

    1746:   Input Parameter:
    1747: . vec - the vector

    1749:   Output Parameters:
    1750: + n - The number of unique entries
    1751: - e - The entries

    1753:   Level: intermediate

    1755: .seealso: `Vec`
    1756: @*/
    1757: PetscErrorCode VecUniqueEntries(Vec vec, PetscInt *n, PetscScalar **e)
    1758: {
    1759:   const PetscScalar *v;
    1760:   PetscScalar       *tmp, *vals;
    1761:   PetscMPIInt       *N, *displs, l;
    1762:   PetscInt           ng, m, i, j, p;
    1763:   PetscMPIInt        size;

    1765:   PetscFunctionBegin;
    1767:   PetscAssertPointer(n, 2);
    1768:   PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)vec), &size));
    1769:   PetscCall(VecGetLocalSize(vec, &m));
    1770:   PetscCall(VecGetArrayRead(vec, &v));
    1771:   PetscCall(PetscMalloc2(m, &tmp, size, &N));
    1772:   for (i = 0, l = 0; i < m; ++i) {
    1773:     /* Can speed this up with sorting */
    1774:     for (j = 0; j < l; ++j) {
    1775:       if (v[i] == tmp[j]) break;
    1776:     }
    1777:     if (j == l) {
    1778:       tmp[j] = v[i];
    1779:       ++l;
    1780:     }
    1781:   }
    1782:   PetscCall(VecRestoreArrayRead(vec, &v));
    1783:   /* Gather serial results */
    1784:   PetscCallMPI(MPI_Allgather(&l, 1, MPI_INT, N, 1, MPI_INT, PetscObjectComm((PetscObject)vec)));
    1785:   for (p = 0, ng = 0; p < size; ++p) ng += N[p];
    1786:   PetscCall(PetscMalloc2(ng, &vals, size + 1, &displs));
    1787:   for (p = 1, displs[0] = 0; p <= size; ++p) displs[p] = displs[p - 1] + N[p - 1];
    1788:   PetscCallMPI(MPI_Allgatherv(tmp, l, MPIU_SCALAR, vals, N, displs, MPIU_SCALAR, PetscObjectComm((PetscObject)vec)));
    1789:   /* Find unique entries */
    1790: #ifdef PETSC_USE_COMPLEX
    1791:   SETERRQ(PetscObjectComm((PetscObject)vec), PETSC_ERR_SUP, "Does not work with complex numbers");
    1792: #else
    1793:   *n = displs[size];
    1794:   PetscCall(PetscSortRemoveDupsReal(n, (PetscReal *)vals));
    1795:   if (e) {
    1796:     PetscAssertPointer(e, 3);
    1797:     PetscCall(PetscMalloc1(*n, e));
    1798:     for (i = 0; i < *n; ++i) (*e)[i] = vals[i];
    1799:   }
    1800:   PetscCall(PetscFree2(vals, displs));
    1801:   PetscCall(PetscFree2(tmp, N));
    1802:   PetscFunctionReturn(PETSC_SUCCESS);
    1803: #endif
    1804: }