Actual source code: dvec2.c
petsc-3.7.1 2016-05-15
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      2: /*
      3:    Defines some vector operation functions that are shared by
      4:   sequential and parallel vectors.
      5: */
      6: #include <../src/vec/vec/impls/dvecimpl.h>
      7: #include <petsc/private/kernels/petscaxpy.h>

     11: #if defined(PETSC_USE_FORTRAN_KERNEL_MDOT)
     12: #include <../src/vec/vec/impls/seq/ftn-kernels/fmdot.h>
     15: PetscErrorCode VecMDot_Seq(Vec xin,PetscInt nv,const Vec yin[],PetscScalar *z)
     16: {
     17:   PetscErrorCode    ierr;
     18:   PetscInt          i,nv_rem,n = xin->map->n;
     19:   PetscScalar       sum0,sum1,sum2,sum3;
     20:   const PetscScalar *yy0,*yy1,*yy2,*yy3,*x;
     21:   Vec               *yy;

     24:   sum0 = 0.0;
     25:   sum1 = 0.0;
     26:   sum2 = 0.0;

     28:   i      = nv;
     29:   nv_rem = nv&0x3;
     30:   yy     = (Vec*)yin;
     31:   VecGetArrayRead(xin,&x);

     33:   switch (nv_rem) {
     34:   case 3:
     35:     VecGetArrayRead(yy[0],&yy0);
     36:     VecGetArrayRead(yy[1],&yy1);
     37:     VecGetArrayRead(yy[2],&yy2);
     38:     fortranmdot3_(x,yy0,yy1,yy2,&n,&sum0,&sum1,&sum2);
     39:     VecRestoreArrayRead(yy[0],&yy0);
     40:     VecRestoreArrayRead(yy[1],&yy1);
     41:     VecRestoreArrayRead(yy[2],&yy2);
     42:     z[0] = sum0;
     43:     z[1] = sum1;
     44:     z[2] = sum2;
     45:     break;
     46:   case 2:
     47:     VecGetArrayRead(yy[0],&yy0);
     48:     VecGetArrayRead(yy[1],&yy1);
     49:     fortranmdot2_(x,yy0,yy1,&n,&sum0,&sum1);
     50:     VecRestoreArrayRead(yy[0],&yy0);
     51:     VecRestoreArrayRead(yy[1],&yy1);
     52:     z[0] = sum0;
     53:     z[1] = sum1;
     54:     break;
     55:   case 1:
     56:     VecGetArrayRead(yy[0],&yy0);
     57:     fortranmdot1_(x,yy0,&n,&sum0);
     58:     VecRestoreArrayRead(yy[0],&yy0);
     59:     z[0] = sum0;
     60:     break;
     61:   case 0:
     62:     break;
     63:   }
     64:   z  += nv_rem;
     65:   i  -= nv_rem;
     66:   yy += nv_rem;

     68:   while (i >0) {
     69:     sum0 = 0.;
     70:     sum1 = 0.;
     71:     sum2 = 0.;
     72:     sum3 = 0.;
     73:     VecGetArrayRead(yy[0],&yy0);
     74:     VecGetArrayRead(yy[1],&yy1);
     75:     VecGetArrayRead(yy[2],&yy2);
     76:     VecGetArrayRead(yy[3],&yy3);
     77:     fortranmdot4_(x,yy0,yy1,yy2,yy3,&n,&sum0,&sum1,&sum2,&sum3);
     78:     VecRestoreArrayRead(yy[0],&yy0);
     79:     VecRestoreArrayRead(yy[1],&yy1);
     80:     VecRestoreArrayRead(yy[2],&yy2);
     81:     VecRestoreArrayRead(yy[3],&yy3);
     82:     yy  += 4;
     83:     z[0] = sum0;
     84:     z[1] = sum1;
     85:     z[2] = sum2;
     86:     z[3] = sum3;
     87:     z   += 4;
     88:     i   -= 4;
     89:   }
     90:   VecRestoreArrayRead(xin,&x);
     91:   PetscLogFlops(PetscMax(nv*(2.0*xin->map->n-1),0.0));
     92:   return(0);
     93: }

     95: #else
     98: PetscErrorCode VecMDot_Seq(Vec xin,PetscInt nv,const Vec yin[],PetscScalar *z)
     99: {
    100:   PetscErrorCode    ierr;
    101:   PetscInt          n = xin->map->n,i,j,nv_rem,j_rem;
    102:   PetscScalar       sum0,sum1,sum2,sum3,x0,x1,x2,x3;
    103:   const PetscScalar *yy0,*yy1,*yy2,*yy3,*x,*xbase;
    104:   Vec               *yy;

    107:   sum0 = 0.;
    108:   sum1 = 0.;
    109:   sum2 = 0.;

    111:   i      = nv;
    112:   nv_rem = nv&0x3;
    113:   yy     = (Vec*)yin;
    114:   j      = n;
    115:   VecGetArrayRead(xin,&xbase);
    116:   x      = xbase;

    118:   switch (nv_rem) {
    119:   case 3:
    120:     VecGetArrayRead(yy[0],&yy0);
    121:     VecGetArrayRead(yy[1],&yy1);
    122:     VecGetArrayRead(yy[2],&yy2);
    123:     switch (j_rem=j&0x3) {
    124:     case 3:
    125:       x2    = x[2];
    126:       sum0 += x2*PetscConj(yy0[2]); sum1 += x2*PetscConj(yy1[2]);
    127:       sum2 += x2*PetscConj(yy2[2]);
    128:     case 2:
    129:       x1    = x[1];
    130:       sum0 += x1*PetscConj(yy0[1]); sum1 += x1*PetscConj(yy1[1]);
    131:       sum2 += x1*PetscConj(yy2[1]);
    132:     case 1:
    133:       x0    = x[0];
    134:       sum0 += x0*PetscConj(yy0[0]); sum1 += x0*PetscConj(yy1[0]);
    135:       sum2 += x0*PetscConj(yy2[0]);
    136:     case 0:
    137:       x   += j_rem;
    138:       yy0 += j_rem;
    139:       yy1 += j_rem;
    140:       yy2 += j_rem;
    141:       j   -= j_rem;
    142:       break;
    143:     }
    144:     while (j>0) {
    145:       x0 = x[0];
    146:       x1 = x[1];
    147:       x2 = x[2];
    148:       x3 = x[3];
    149:       x += 4;

    151:       sum0 += x0*PetscConj(yy0[0]) + x1*PetscConj(yy0[1]) + x2*PetscConj(yy0[2]) + x3*PetscConj(yy0[3]); yy0+=4;
    152:       sum1 += x0*PetscConj(yy1[0]) + x1*PetscConj(yy1[1]) + x2*PetscConj(yy1[2]) + x3*PetscConj(yy1[3]); yy1+=4;
    153:       sum2 += x0*PetscConj(yy2[0]) + x1*PetscConj(yy2[1]) + x2*PetscConj(yy2[2]) + x3*PetscConj(yy2[3]); yy2+=4;
    154:       j    -= 4;
    155:     }
    156:     z[0] = sum0;
    157:     z[1] = sum1;
    158:     z[2] = sum2;
    159:     VecRestoreArrayRead(yy[0],&yy0);
    160:     VecRestoreArrayRead(yy[1],&yy1);
    161:     VecRestoreArrayRead(yy[2],&yy2);
    162:     break;
    163:   case 2:
    164:     VecGetArrayRead(yy[0],&yy0);
    165:     VecGetArrayRead(yy[1],&yy1);
    166:     switch (j_rem=j&0x3) {
    167:     case 3:
    168:       x2    = x[2];
    169:       sum0 += x2*PetscConj(yy0[2]); sum1 += x2*PetscConj(yy1[2]);
    170:     case 2:
    171:       x1    = x[1];
    172:       sum0 += x1*PetscConj(yy0[1]); sum1 += x1*PetscConj(yy1[1]);
    173:     case 1:
    174:       x0    = x[0];
    175:       sum0 += x0*PetscConj(yy0[0]); sum1 += x0*PetscConj(yy1[0]);
    176:     case 0:
    177:       x   += j_rem;
    178:       yy0 += j_rem;
    179:       yy1 += j_rem;
    180:       j   -= j_rem;
    181:       break;
    182:     }
    183:     while (j>0) {
    184:       x0 = x[0];
    185:       x1 = x[1];
    186:       x2 = x[2];
    187:       x3 = x[3];
    188:       x += 4;

    190:       sum0 += x0*PetscConj(yy0[0]) + x1*PetscConj(yy0[1]) + x2*PetscConj(yy0[2]) + x3*PetscConj(yy0[3]); yy0+=4;
    191:       sum1 += x0*PetscConj(yy1[0]) + x1*PetscConj(yy1[1]) + x2*PetscConj(yy1[2]) + x3*PetscConj(yy1[3]); yy1+=4;
    192:       j    -= 4;
    193:     }
    194:     z[0] = sum0;
    195:     z[1] = sum1;

    197:     VecRestoreArrayRead(yy[0],&yy0);
    198:     VecRestoreArrayRead(yy[1],&yy1);
    199:     break;
    200:   case 1:
    201:     VecGetArrayRead(yy[0],&yy0);
    202:     switch (j_rem=j&0x3) {
    203:     case 3:
    204:       x2 = x[2]; sum0 += x2*PetscConj(yy0[2]);
    205:     case 2:
    206:       x1 = x[1]; sum0 += x1*PetscConj(yy0[1]);
    207:     case 1:
    208:       x0 = x[0]; sum0 += x0*PetscConj(yy0[0]);
    209:     case 0:
    210:       x   += j_rem;
    211:       yy0 += j_rem;
    212:       j   -= j_rem;
    213:       break;
    214:     }
    215:     while (j>0) {
    216:       sum0 += x[0]*PetscConj(yy0[0]) + x[1]*PetscConj(yy0[1])
    217:             + x[2]*PetscConj(yy0[2]) + x[3]*PetscConj(yy0[3]);
    218:       yy0  +=4;
    219:       j    -= 4; x+=4;
    220:     }
    221:     z[0] = sum0;

    223:     VecRestoreArrayRead(yy[0],&yy0);
    224:     break;
    225:   case 0:
    226:     break;
    227:   }
    228:   z  += nv_rem;
    229:   i  -= nv_rem;
    230:   yy += nv_rem;

    232:   while (i >0) {
    233:     sum0 = 0.;
    234:     sum1 = 0.;
    235:     sum2 = 0.;
    236:     sum3 = 0.;
    237:     VecGetArrayRead(yy[0],&yy0);
    238:     VecGetArrayRead(yy[1],&yy1);
    239:     VecGetArrayRead(yy[2],&yy2);
    240:     VecGetArrayRead(yy[3],&yy3);

    242:     j = n;
    243:     x = xbase;
    244:     switch (j_rem=j&0x3) {
    245:     case 3:
    246:       x2    = x[2];
    247:       sum0 += x2*PetscConj(yy0[2]); sum1 += x2*PetscConj(yy1[2]);
    248:       sum2 += x2*PetscConj(yy2[2]); sum3 += x2*PetscConj(yy3[2]);
    249:     case 2:
    250:       x1    = x[1];
    251:       sum0 += x1*PetscConj(yy0[1]); sum1 += x1*PetscConj(yy1[1]);
    252:       sum2 += x1*PetscConj(yy2[1]); sum3 += x1*PetscConj(yy3[1]);
    253:     case 1:
    254:       x0    = x[0];
    255:       sum0 += x0*PetscConj(yy0[0]); sum1 += x0*PetscConj(yy1[0]);
    256:       sum2 += x0*PetscConj(yy2[0]); sum3 += x0*PetscConj(yy3[0]);
    257:     case 0:
    258:       x   += j_rem;
    259:       yy0 += j_rem;
    260:       yy1 += j_rem;
    261:       yy2 += j_rem;
    262:       yy3 += j_rem;
    263:       j   -= j_rem;
    264:       break;
    265:     }
    266:     while (j>0) {
    267:       x0 = x[0];
    268:       x1 = x[1];
    269:       x2 = x[2];
    270:       x3 = x[3];
    271:       x += 4;

    273:       sum0 += x0*PetscConj(yy0[0]) + x1*PetscConj(yy0[1]) + x2*PetscConj(yy0[2]) + x3*PetscConj(yy0[3]); yy0+=4;
    274:       sum1 += x0*PetscConj(yy1[0]) + x1*PetscConj(yy1[1]) + x2*PetscConj(yy1[2]) + x3*PetscConj(yy1[3]); yy1+=4;
    275:       sum2 += x0*PetscConj(yy2[0]) + x1*PetscConj(yy2[1]) + x2*PetscConj(yy2[2]) + x3*PetscConj(yy2[3]); yy2+=4;
    276:       sum3 += x0*PetscConj(yy3[0]) + x1*PetscConj(yy3[1]) + x2*PetscConj(yy3[2]) + x3*PetscConj(yy3[3]); yy3+=4;
    277:       j    -= 4;
    278:     }
    279:     z[0] = sum0;
    280:     z[1] = sum1;
    281:     z[2] = sum2;
    282:     z[3] = sum3;
    283:     z   += 4;
    284:     i   -= 4;
    285:     VecRestoreArrayRead(yy[0],&yy0);
    286:     VecRestoreArrayRead(yy[1],&yy1);
    287:     VecRestoreArrayRead(yy[2],&yy2);
    288:     VecRestoreArrayRead(yy[3],&yy3);
    289:     yy  += 4;
    290:   }
    291:   VecRestoreArrayRead(xin,&xbase);
    292:   PetscLogFlops(PetscMax(nv*(2.0*xin->map->n-1),0.0));
    293:   return(0);
    294: }
    295: #endif

    297: /* ----------------------------------------------------------------------------*/
    300: PetscErrorCode VecMTDot_Seq(Vec xin,PetscInt nv,const Vec yin[],PetscScalar *z)
    301: {
    302:   PetscErrorCode    ierr;
    303:   PetscInt          n = xin->map->n,i,j,nv_rem,j_rem;
    304:   PetscScalar       sum0,sum1,sum2,sum3,x0,x1,x2,x3;
    305:   const PetscScalar *yy0,*yy1,*yy2,*yy3,*x,*xbase;
    306:   Vec               *yy;

    309:   sum0 = 0.;
    310:   sum1 = 0.;
    311:   sum2 = 0.;

    313:   i      = nv;
    314:   nv_rem = nv&0x3;
    315:   yy     = (Vec*)yin;
    316:   j      = n;
    317:   VecGetArrayRead(xin,&xbase);
    318:   x      = xbase;

    320:   switch (nv_rem) {
    321:   case 3:
    322:     VecGetArrayRead(yy[0],&yy0);
    323:     VecGetArrayRead(yy[1],&yy1);
    324:     VecGetArrayRead(yy[2],&yy2);
    325:     switch (j_rem=j&0x3) {
    326:     case 3:
    327:       x2    = x[2];
    328:       sum0 += x2*yy0[2]; sum1 += x2*yy1[2];
    329:       sum2 += x2*yy2[2];
    330:     case 2:
    331:       x1    = x[1];
    332:       sum0 += x1*yy0[1]; sum1 += x1*yy1[1];
    333:       sum2 += x1*yy2[1];
    334:     case 1:
    335:       x0    = x[0];
    336:       sum0 += x0*yy0[0]; sum1 += x0*yy1[0];
    337:       sum2 += x0*yy2[0];
    338:     case 0:
    339:       x   += j_rem;
    340:       yy0 += j_rem;
    341:       yy1 += j_rem;
    342:       yy2 += j_rem;
    343:       j   -= j_rem;
    344:       break;
    345:     }
    346:     while (j>0) {
    347:       x0 = x[0];
    348:       x1 = x[1];
    349:       x2 = x[2];
    350:       x3 = x[3];
    351:       x += 4;

    353:       sum0 += x0*yy0[0] + x1*yy0[1] + x2*yy0[2] + x3*yy0[3]; yy0+=4;
    354:       sum1 += x0*yy1[0] + x1*yy1[1] + x2*yy1[2] + x3*yy1[3]; yy1+=4;
    355:       sum2 += x0*yy2[0] + x1*yy2[1] + x2*yy2[2] + x3*yy2[3]; yy2+=4;
    356:       j    -= 4;
    357:     }
    358:     z[0] = sum0;
    359:     z[1] = sum1;
    360:     z[2] = sum2;
    361:     VecRestoreArrayRead(yy[0],&yy0);
    362:     VecRestoreArrayRead(yy[1],&yy1);
    363:     VecRestoreArrayRead(yy[2],&yy2);
    364:     break;
    365:   case 2:
    366:     VecGetArrayRead(yy[0],&yy0);
    367:     VecGetArrayRead(yy[1],&yy1);
    368:     switch (j_rem=j&0x3) {
    369:     case 3:
    370:       x2    = x[2];
    371:       sum0 += x2*yy0[2]; sum1 += x2*yy1[2];
    372:     case 2:
    373:       x1    = x[1];
    374:       sum0 += x1*yy0[1]; sum1 += x1*yy1[1];
    375:     case 1:
    376:       x0    = x[0];
    377:       sum0 += x0*yy0[0]; sum1 += x0*yy1[0];
    378:     case 0:
    379:       x   += j_rem;
    380:       yy0 += j_rem;
    381:       yy1 += j_rem;
    382:       j   -= j_rem;
    383:       break;
    384:     }
    385:     while (j>0) {
    386:       x0 = x[0];
    387:       x1 = x[1];
    388:       x2 = x[2];
    389:       x3 = x[3];
    390:       x += 4;

    392:       sum0 += x0*yy0[0] + x1*yy0[1] + x2*yy0[2] + x3*yy0[3]; yy0+=4;
    393:       sum1 += x0*yy1[0] + x1*yy1[1] + x2*yy1[2] + x3*yy1[3]; yy1+=4;
    394:       j    -= 4;
    395:     }
    396:     z[0] = sum0;
    397:     z[1] = sum1;

    399:     VecRestoreArrayRead(yy[0],&yy0);
    400:     VecRestoreArrayRead(yy[1],&yy1);
    401:     break;
    402:   case 1:
    403:     VecGetArrayRead(yy[0],&yy0);
    404:     switch (j_rem=j&0x3) {
    405:     case 3:
    406:       x2 = x[2]; sum0 += x2*yy0[2];
    407:     case 2:
    408:       x1 = x[1]; sum0 += x1*yy0[1];
    409:     case 1:
    410:       x0 = x[0]; sum0 += x0*yy0[0];
    411:     case 0:
    412:       x   += j_rem;
    413:       yy0 += j_rem;
    414:       j   -= j_rem;
    415:       break;
    416:     }
    417:     while (j>0) {
    418:       sum0 += x[0]*yy0[0] + x[1]*yy0[1] + x[2]*yy0[2] + x[3]*yy0[3]; yy0+=4;
    419:       j    -= 4; x+=4;
    420:     }
    421:     z[0] = sum0;

    423:     VecRestoreArrayRead(yy[0],&yy0);
    424:     break;
    425:   case 0:
    426:     break;
    427:   }
    428:   z  += nv_rem;
    429:   i  -= nv_rem;
    430:   yy += nv_rem;

    432:   while (i >0) {
    433:     sum0 = 0.;
    434:     sum1 = 0.;
    435:     sum2 = 0.;
    436:     sum3 = 0.;
    437:     VecGetArrayRead(yy[0],&yy0);
    438:     VecGetArrayRead(yy[1],&yy1);
    439:     VecGetArrayRead(yy[2],&yy2);
    440:     VecGetArrayRead(yy[3],&yy3);
    441:     x    = xbase;

    443:     j = n;
    444:     switch (j_rem=j&0x3) {
    445:     case 3:
    446:       x2    = x[2];
    447:       sum0 += x2*yy0[2]; sum1 += x2*yy1[2];
    448:       sum2 += x2*yy2[2]; sum3 += x2*yy3[2];
    449:     case 2:
    450:       x1    = x[1];
    451:       sum0 += x1*yy0[1]; sum1 += x1*yy1[1];
    452:       sum2 += x1*yy2[1]; sum3 += x1*yy3[1];
    453:     case 1:
    454:       x0    = x[0];
    455:       sum0 += x0*yy0[0]; sum1 += x0*yy1[0];
    456:       sum2 += x0*yy2[0]; sum3 += x0*yy3[0];
    457:     case 0:
    458:       x   += j_rem;
    459:       yy0 += j_rem;
    460:       yy1 += j_rem;
    461:       yy2 += j_rem;
    462:       yy3 += j_rem;
    463:       j   -= j_rem;
    464:       break;
    465:     }
    466:     while (j>0) {
    467:       x0 = x[0];
    468:       x1 = x[1];
    469:       x2 = x[2];
    470:       x3 = x[3];
    471:       x += 4;

    473:       sum0 += x0*yy0[0] + x1*yy0[1] + x2*yy0[2] + x3*yy0[3]; yy0+=4;
    474:       sum1 += x0*yy1[0] + x1*yy1[1] + x2*yy1[2] + x3*yy1[3]; yy1+=4;
    475:       sum2 += x0*yy2[0] + x1*yy2[1] + x2*yy2[2] + x3*yy2[3]; yy2+=4;
    476:       sum3 += x0*yy3[0] + x1*yy3[1] + x2*yy3[2] + x3*yy3[3]; yy3+=4;
    477:       j    -= 4;
    478:     }
    479:     z[0] = sum0;
    480:     z[1] = sum1;
    481:     z[2] = sum2;
    482:     z[3] = sum3;
    483:     z   += 4;
    484:     i   -= 4;
    485:     VecRestoreArrayRead(yy[0],&yy0);
    486:     VecRestoreArrayRead(yy[1],&yy1);
    487:     VecRestoreArrayRead(yy[2],&yy2);
    488:     VecRestoreArrayRead(yy[3],&yy3);
    489:     yy  += 4;
    490:   }
    491:   VecRestoreArrayRead(xin,&xbase);
    492:   PetscLogFlops(PetscMax(nv*(2.0*xin->map->n-1),0.0));
    493:   return(0);
    494: }

    499: PetscErrorCode VecMax_Seq(Vec xin,PetscInt *idx,PetscReal *z)
    500: {
    501:   PetscInt          i,j=0,n = xin->map->n;
    502:   PetscReal         max,tmp;
    503:   const PetscScalar *xx;
    504:   PetscErrorCode    ierr;

    507:   VecGetArrayRead(xin,&xx);
    508:   if (!n) {
    509:     max = PETSC_MIN_REAL;
    510:     j   = -1;
    511:   } else {
    512:     max = PetscRealPart(*xx++); j = 0;
    513:     for (i=1; i<n; i++) {
    514:       if ((tmp = PetscRealPart(*xx++)) > max) { j = i; max = tmp;}
    515:     }
    516:   }
    517:   *z = max;
    518:   if (idx) *idx = j;
    519:   VecRestoreArrayRead(xin,&xx);
    520:   return(0);
    521: }

    525: PetscErrorCode VecMin_Seq(Vec xin,PetscInt *idx,PetscReal *z)
    526: {
    527:   PetscInt          i,j=0,n = xin->map->n;
    528:   PetscReal         min,tmp;
    529:   const PetscScalar *xx;
    530:   PetscErrorCode    ierr;

    533:   VecGetArrayRead(xin,&xx);
    534:   if (!n) {
    535:     min = PETSC_MAX_REAL;
    536:     j   = -1;
    537:   } else {
    538:     min = PetscRealPart(*xx++); j = 0;
    539:     for (i=1; i<n; i++) {
    540:       if ((tmp = PetscRealPart(*xx++)) < min) { j = i; min = tmp;}
    541:     }
    542:   }
    543:   *z = min;
    544:   if (idx) *idx = j;
    545:   VecRestoreArrayRead(xin,&xx);
    546:   return(0);
    547: }

    551: PetscErrorCode VecSet_Seq(Vec xin,PetscScalar alpha)
    552: {
    553:   PetscInt       i,n = xin->map->n;
    554:   PetscScalar    *xx;

    558:   VecGetArray(xin,&xx);
    559:   if (alpha == (PetscScalar)0.0) {
    560:     PetscMemzero(xx,n*sizeof(PetscScalar));
    561:   } else {
    562:     for (i=0; i<n; i++) xx[i] = alpha;
    563:   }
    564:   VecRestoreArray(xin,&xx);
    565:   return(0);
    566: }

    570: PetscErrorCode VecMAXPY_Seq(Vec xin, PetscInt nv,const PetscScalar *alpha,Vec *y)
    571: {
    572:   PetscErrorCode    ierr;
    573:   PetscInt          n = xin->map->n,j,j_rem;
    574:   const PetscScalar *yy0,*yy1,*yy2,*yy3;
    575:   PetscScalar       *xx,alpha0,alpha1,alpha2,alpha3;

    577: #if defined(PETSC_HAVE_PRAGMA_DISJOINT)
    578: #pragma disjoint(*xx,*yy0,*yy1,*yy2,*yy3,*alpha)
    579: #endif

    582:   PetscLogFlops(nv*2.0*n);
    583:   VecGetArray(xin,&xx);
    584:   switch (j_rem=nv&0x3) {
    585:   case 3:
    586:     VecGetArrayRead(y[0],&yy0);
    587:     VecGetArrayRead(y[1],&yy1);
    588:     VecGetArrayRead(y[2],&yy2);
    589:     alpha0 = alpha[0];
    590:     alpha1 = alpha[1];
    591:     alpha2 = alpha[2];
    592:     alpha += 3;
    593:     PetscKernelAXPY3(xx,alpha0,alpha1,alpha2,yy0,yy1,yy2,n);
    594:     VecRestoreArrayRead(y[0],&yy0);
    595:     VecRestoreArrayRead(y[1],&yy1);
    596:     VecRestoreArrayRead(y[2],&yy2);
    597:     y   += 3;
    598:     break;
    599:   case 2:
    600:     VecGetArrayRead(y[0],&yy0);
    601:     VecGetArrayRead(y[1],&yy1);
    602:     alpha0 = alpha[0];
    603:     alpha1 = alpha[1];
    604:     alpha +=2;
    605:     PetscKernelAXPY2(xx,alpha0,alpha1,yy0,yy1,n);
    606:     VecRestoreArrayRead(y[0],&yy0);
    607:     VecRestoreArrayRead(y[1],&yy1);
    608:     y   +=2;
    609:     break;
    610:   case 1:
    611:     VecGetArrayRead(y[0],&yy0);
    612:     alpha0 = *alpha++;
    613:     PetscKernelAXPY(xx,alpha0,yy0,n);
    614:     VecRestoreArrayRead(y[0],&yy0);
    615:     y   +=1;
    616:     break;
    617:   }
    618:   for (j=j_rem; j<nv; j+=4) {
    619:     VecGetArrayRead(y[0],&yy0);
    620:     VecGetArrayRead(y[1],&yy1);
    621:     VecGetArrayRead(y[2],&yy2);
    622:     VecGetArrayRead(y[3],&yy3);
    623:     alpha0 = alpha[0];
    624:     alpha1 = alpha[1];
    625:     alpha2 = alpha[2];
    626:     alpha3 = alpha[3];
    627:     alpha += 4;

    629:     PetscKernelAXPY4(xx,alpha0,alpha1,alpha2,alpha3,yy0,yy1,yy2,yy3,n);
    630:     VecRestoreArrayRead(y[0],&yy0);
    631:     VecRestoreArrayRead(y[1],&yy1);
    632:     VecRestoreArrayRead(y[2],&yy2);
    633:     VecRestoreArrayRead(y[3],&yy3);
    634:     y   += 4;
    635:   }
    636:   VecRestoreArray(xin,&xx);
    637:   return(0);
    638: }

    640: #include <../src/vec/vec/impls/seq/ftn-kernels/faypx.h>

    644: PetscErrorCode VecAYPX_Seq(Vec yin,PetscScalar alpha,Vec xin)
    645: {
    646:   PetscErrorCode    ierr;
    647:   PetscInt          n = yin->map->n;
    648:   PetscScalar       *yy;
    649:   const PetscScalar *xx;

    652:   if (alpha == (PetscScalar)0.0) {
    653:     VecCopy(xin,yin);
    654:   } else if (alpha == (PetscScalar)1.0) {
    655:     VecAXPY_Seq(yin,alpha,xin);
    656:   } else if (alpha == (PetscScalar)-1.0) {
    657:     PetscInt i;
    658:     VecGetArrayRead(xin,&xx);
    659:     VecGetArray(yin,&yy);

    661:     for (i=0; i<n; i++) yy[i] = xx[i] - yy[i];

    663:     VecRestoreArrayRead(xin,&xx);
    664:     VecRestoreArray(yin,&yy);
    665:     PetscLogFlops(1.0*n);
    666:   } else {
    667:     VecGetArrayRead(xin,&xx);
    668:     VecGetArray(yin,&yy);
    669: #if defined(PETSC_USE_FORTRAN_KERNEL_AYPX)
    670:     {
    671:       PetscScalar oalpha = alpha;
    672:       fortranaypx_(&n,&oalpha,xx,yy);
    673:     }
    674: #else
    675:     {
    676:       PetscInt i;

    678:       for (i=0; i<n; i++) yy[i] = xx[i] + alpha*yy[i];
    679:     }
    680: #endif
    681:     VecRestoreArrayRead(xin,&xx);
    682:     VecRestoreArray(yin,&yy);
    683:     PetscLogFlops(2.0*n);
    684:   }
    685:   return(0);
    686: }

    688: #include <../src/vec/vec/impls/seq/ftn-kernels/fwaxpy.h>
    689: /*
    690:    IBM ESSL contains a routine dzaxpy() that is our WAXPY() but it appears
    691:   to be slower than a regular C loop.  Hence,we do not include it.
    692:   void ?zaxpy(int*,PetscScalar*,PetscScalar*,int*,PetscScalar*,int*,PetscScalar*,int*);
    693: */

    697: PetscErrorCode VecWAXPY_Seq(Vec win, PetscScalar alpha,Vec xin,Vec yin)
    698: {
    699:   PetscErrorCode     ierr;
    700:   PetscInt           i,n = win->map->n;
    701:   PetscScalar        *ww;
    702:   const PetscScalar  *yy,*xx;

    705:   VecGetArrayRead(xin,&xx);
    706:   VecGetArrayRead(yin,&yy);
    707:   VecGetArray(win,&ww);
    708:   if (alpha == (PetscScalar)1.0) {
    709:     PetscLogFlops(n);
    710:     /* could call BLAS axpy after call to memcopy, but may be slower */
    711:     for (i=0; i<n; i++) ww[i] = yy[i] + xx[i];
    712:   } else if (alpha == (PetscScalar)-1.0) {
    713:     PetscLogFlops(n);
    714:     for (i=0; i<n; i++) ww[i] = yy[i] - xx[i];
    715:   } else if (alpha == (PetscScalar)0.0) {
    716:     PetscMemcpy(ww,yy,n*sizeof(PetscScalar));
    717:   } else {
    718:     PetscScalar oalpha = alpha;
    719: #if defined(PETSC_USE_FORTRAN_KERNEL_WAXPY)
    720:     fortranwaxpy_(&n,&oalpha,xx,yy,ww);
    721: #else
    722:     for (i=0; i<n; i++) ww[i] = yy[i] + oalpha * xx[i];
    723: #endif
    724:     PetscLogFlops(2.0*n);
    725:   }
    726:   VecRestoreArrayRead(xin,&xx);
    727:   VecRestoreArrayRead(yin,&yy);
    728:   VecRestoreArray(win,&ww);
    729:   return(0);
    730: }

    734: PetscErrorCode VecMaxPointwiseDivide_Seq(Vec xin,Vec yin,PetscReal *max)
    735: {
    736:   PetscErrorCode    ierr;
    737:   PetscInt          n = xin->map->n,i;
    738:   const PetscScalar *xx,*yy;
    739:   PetscReal         m = 0.0;

    742:   VecGetArrayRead(xin,&xx);
    743:   VecGetArrayRead(yin,&yy);
    744:   for (i = 0; i < n; i++) {
    745:     if (yy[i] != (PetscScalar)0.0) {
    746:       m = PetscMax(PetscAbsScalar(xx[i]/yy[i]), m);
    747:     } else {
    748:       m = PetscMax(PetscAbsScalar(xx[i]), m);
    749:     }
    750:   }
    751:   VecRestoreArrayRead(xin,&xx);
    752:   VecRestoreArrayRead(yin,&yy);
    753:   MPIU_Allreduce(&m,max,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)xin));
    754:   PetscLogFlops(n);
    755:   return(0);
    756: }

    760: PetscErrorCode VecPlaceArray_Seq(Vec vin,const PetscScalar *a)
    761: {
    762:   Vec_Seq *v = (Vec_Seq*)vin->data;

    765:   if (v->unplacedarray) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"VecPlaceArray() was already called on this vector, without a call to VecResetArray()");
    766:   v->unplacedarray = v->array;  /* save previous array so reset can bring it back */
    767:   v->array         = (PetscScalar*)a;
    768:   return(0);
    769: }

    773: PetscErrorCode VecReplaceArray_Seq(Vec vin,const PetscScalar *a)
    774: {
    775:   Vec_Seq        *v = (Vec_Seq*)vin->data;

    779:   PetscFree(v->array_allocated);
    780:   v->array_allocated = v->array = (PetscScalar*)a;
    781:   return(0);
    782: }