[petsc-users] DMGlobalToLocal acting weird

[Smith, Barry F.]

> On Jul 2, 2018, at 6:13 PM, Manuel Valera <mvalera-w at sdsu.edu> wrote:
> 
> Ok so i fixed the '99 business' by making sure the whole DMDA array was filled, there was row at the end that wasn't and hence that problem,
> 
> The local vector problem persists, though,

  Exactly what error? When you print the entire local vector it doesn't match the global vector? Or something else. 

  DMGlobalToLocalBegin/End() are used in dozens of tests in PETSc; very unlikely there is a bug that is causing you a problem especially on one process where it just copies the values from the global vector to the local vector.


> i solved it for now using a global vector instead of a local one, is this because of the warning on globaltolocalbegin/end? 
> 
> Thanks,
> 
> 
> 
> On Mon, Jul 2, 2018 at 3:42 PM, Manuel Valera <mvalera-w at sdsu.edu> wrote:
> 
> 
> On Mon, Jul 2, 2018 at 3:04 PM, Smith, Barry F. <bsmith at mcs.anl.gov> wrote:
> 
>    First make sure that getCenterInfo(daScalars,  xstart, ystart, zstart, xend, yend, zend) returns what it should. 
> 
> It does, i am also working in one processor only for now.
> 
>  
>    remove the 99 business and print out the arrtemp() and TO() values. Are they correct?
> 
> They are not, i'm using maximum and minimum as probes to print into, but the minimum of T0 is 1 and is 0 for arrtemp, 
>  
> 
>    What is DimTemperature? Shouldn't it be LocTempature?
> 
> Yes, sorry about that,
>  
> 
>    Print out the values in tdim().
> 
> Yes, the same as with arrtemp/T0
> 
> Sorry i didn't mention i was debugging by printing the extremas of the arrays,
> 
> From your answer you seem to think the problem is in my code's side and it may very well be, but from the DMGlobalToLocalBegin there is a warning saying INSERT_VALUES doesn't work with DMDAs, is this still an issue or have been fixed? i understand it looks like these are two different problems in my code,
> 
> Thanks,
> 
> 
> 
> 
> 
> 
> 
> 
> 
>  
> 
>    Barry
> 
> 
> 
> 
> > On Jul 2, 2018, at 2:58 PM, Manuel Valera <mvalera-w at sdsu.edu> wrote:
> > 
> > Hi guys,
> > 
> > I've noticed a bug in my code that seems to happen right after a call to DMGlobalToLocalBegin/End and i can't seem to find a reason, it goes like this:
> > 
> > I create the DMDA (daScalars) with the following: 
> > 
> >  bx = DM_BOUNDARY_GHOSTED
> >  by = DM_BOUNDARY_PERIODIC
> >  bz = DM_BOUNDARY_GHOSTED
> >  dof = 1
> >  stw = 3
> > call DMDACreate3d(PETSC_COMM_WORLD,bx,by,bz,DMDA_STENCIL_BOX,gridx,gridy,gridz,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE, &                                dof,stw,PETSC_NULL_INTEGER,PETSC_NULL_INTEGER,PETSC_NULL_INTEGER,daScalars,ierr)
> > call DMSetFromOptions(daScalars,ierr)
> > call DMSetUp(daScalars,ierr)
> > 
> > Then i read from a file the temperature and salinity fields of my problems, those two are giving the trouble, i do it with this template:
> > 
> > call DMCreateGlobalVector(daScalars,gTemperature,ierr)
> > call DMDAVecGetArrayF90(daScalars,gTemperature,arrtemp,ierr)
> >    arrtemp = 99.0d0      !no idea why this fixes the problem -mv 62518
> > call getCenterInfo(daScalars,  xstart, ystart, zstart, xend, yend, zend)
> >             do k=zstart,zend-1
> >                 do j=ystart,yend-1
> >                     do i=xstart,xend-1
> >                         arrtemp(i,j,k) = T0(i+1,j+1,k+1)
> >                     enddo
> >                 enddo
> >             enddo
> > call DMDAVecRestoreArrayF90(daScalars,gTemperature,arrtemp,ierr)
> > call DMCreateLocalVector(daScalars,LocTemperature,ierr)
> > call DMGlobalToLocalBegin(daScalars,gTemperature,INSERT_VALUES,LocTemperature,ierr)
> > call DMGlobalToLocalEnd(daScalars,gTemperature,INSERT_VALUES,LocTemperature,ierr)
> > 
> > 
> > Now here is the first weirdness, if i assign a number to my array it does behave as it should for the global quantity, but it must be a greater number than the maximum of the field for this to happen, so i assign 99.0 arbitrarily, otherwise it doesn't read the array correctly, but it does as of now,
> > 
> > Next, the last two lines communicate the array to the local counterparts, but when i read LocTemperature with:
> > 
> >     call DMDAVecGetArrayReadF90(daScalars,DimTemperature,tdim,ierr)
> >     print*,'Copied MinT0: ', minval(tdim)
> >     call DMDAVecRestoreArrayReadF90(daScalars,DimTemperature,tdim,ierr)
> > 
> > That array minimum doesn't coincide with the global minimum, it should be 1.000 but it is just 0.000, the same happens with the Salinity following an identical approach,
> > 
> > Any ideas on where to start looking? i have last month's PETSc build,
> > 
> > I'm running in 1 processor for now,
> > 
> > Thanks,
> > 
> > Manuel
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> 
> 
>