[petsc-users] Fwd: Re: Problem with fortran version of ex29 in ksp
Matthew Knepley
knepley at gmail.com
Fri May 4 10:17:21 CDT 2012
On Fri, May 4, 2012 at 11:05 AM, TAY wee-beng <zonexo at gmail.com> wrote:
>
> On 4/5/2012 3:05 PM, Matthew Knepley wrote:
>
> On Fri, May 4, 2012 at 8:59 AM, TAY wee-beng <zonexo at gmail.com> wrote:
>
>>
>> Hi,
>>
>> Is there anything else I can try to get it working right?
>>
>
> The MatGetNullSpaceRemove() is missing.
>
> Where should I add MatGetNullSpaceRemove and what are its syntax? I
> googled but there's no results.
>
Fixed in p;etsc-dev:
http://www.mcs.anl.gov/petsc/petsc-dev/docs/manualpages/Mat/MatNullSpaceRemove.html
Matt
> Thanks.
>
>
> Matt
>
>
>> Thanks！
>>
>>
>> On 2/5/2012 10:11 PM, Matthew Knepley wrote:
>>
>> On Wed, May 2, 2012 at 1:55 PM, TAY wee-beng <zonexo at gmail.com> wrote:
>>
>>> Hi,
>>>
>>> I did a MatView and VecView on both C and Fortran, right after Mat and
>>> Vec assembly. I have attached the printout below. They are exactly the
>>> same, but yet the result is different in Neumann condition. However, the
>>> dirichlet condition gives the correct ans. Is there anything else that
>>> could be wrong even if the Mat and Vec are the same?
>>>
>>
>> Did you set the null space for the matrix when you have Neumann
>> conditions?
>>
>> Yes, for the matrix, I set as:
>>
>> call
>> MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL_OBJECT,nullspace,ierr)
>>
>> call MatSetNullSpace(jac,nullspace,ierr)
>>
>> call MatNullSpaceDestroy(nullspace,ierr)
>>
>> for the Vec,
>>
>> call
>> MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL_OBJECT,nullspace,ierr)
>>
>> *!call MatNullSpaceRemove(nullspace,b,PETSC_NULL,ierr)*
>>
>> call MatNullSpaceDestroy(nullspace,ierr)
>>
>> MatNullSpaceRemove was comment out because there's error during linking
>>
>>
>>
>> Matt
>>
>>
>>> Thanks!
>>>
>>> Fortran:
>>>
>>> Matrix Object: 1 MPI processes
>>> type: seqaij
>>> row 0: (0, 2) (1, -1) (3, -1)
>>> row 1: (0, -1) (1, 3) (2, -1) (4, -1)
>>> row 2: (1, -1) (2, 2) (5, -1)
>>> row 3: (0, -1) (3, 3) (4, -1) (6, -1)
>>> row 4: (1, -1) (3, -1) (4, 4) (5, -1) (7, -1)
>>> row 5: (2, -1) (4, -1) (5, 3) (8, -1)
>>> row 6: (3, -1) (6, 2) (7, -1)
>>> row 7: (4, -1) (6, -1) (7, 3) (8, -1)
>>> row 8: (5, -1) (7, -1) (8, 2)
>>> Vector Object:Vec_0000000084000000_0 1 MPI processes
>>> type: mpi
>>> Process [0]
>>> 0.25
>>> 0.0205213
>>> 1.135e-005
>>> 0.0205213
>>> 0.00168449
>>> 9.31663e-007
>>> 1.135e-005
>>> 9.31663e-007
>>> 5.15289e-010
>>> Vector Object:Vec_0000000084000000_1 1 MPI processes
>>> type: mpi
>>> Process [0]
>>> 0.14924
>>> 0.0242397
>>> -0.0260347
>>> 0.0242397
>>> -0.0256192
>>> -0.0400102
>>> -0.0260347
>>> -0.0400102
>>> -0.0400102
>>> Press any key to continue . . .
>>>
>>> C:
>>>
>>> Matrix Object: 1 MPI processes
>>> type: seqaij
>>> row 0: (0, 2) (1, -1) (3, -1)
>>> row 1: (0, -1) (1, 3) (2, -1) (4, -1)
>>> row 2: (1, -1) (2, 2) (5, -1)
>>> row 3: (0, -1) (3, 3) (4, -1) (6, -1)
>>> row 4: (1, -1) (3, -1) (4, 4) (5, -1) (7, -1)
>>> row 5: (2, -1) (4, -1) (5, 3) (8, -1)
>>> row 6: (3, -1) (6, 2) (7, -1)
>>> row 7: (4, -1) (6, -1) (7, 3) (8, -1)
>>> row 8: (5, -1) (7, -1) (8, 2)
>>> Vector Object:Vec_0x1d3b000_0 1 MPI processes
>>> type: mpi
>>> Process [0]
>>> 0.25
>>> 0.0205212
>>> 1.135e-05
>>> 0.0205212
>>> 0.00168449
>>> 9.31663e-07
>>> 1.135e-05
>>> 9.31663e-07
>>> 5.15288e-10
>>> Vector Object:Vec_0x1d3b000_1 1 MPI processes
>>> type: mpi
>>> Process [0]
>>> 0.139311
>>> 0.0305751
>>> -0.0220633
>>> 0.0305751
>>> -0.0135158
>>> -0.042185
>>> -0.0220633
>>> -0.042185
>>> -0.058449
>>>
>>>
>>>
>>> Yours sincerely,
>>>
>>> TAY wee-beng
>>>
>>>
>>> On 1/5/2012 11:54 PM, Matthew Knepley wrote:
>>>
>>> On Tue, May 1, 2012 at 5:48 PM, TAY wee-beng <zonexo at gmail.com> wrote:
>>>
>>>> Hi,
>>>>
>>>> Do you mean my method is wrong?
>>>>
>>>> I am following the template of ex22f,
>>>>
>>>> where the variables are declared as :
>>>>
>>>> PetscScalar v(5)
>>>>
>>>> MatStencil row(4),col(4,5)
>>>>
>>>> Hence,
>>>>
>>>> for the neumann BC
>>>>
>>>> num = 1
>>>>
>>>> if (j/=0) then
>>>>
>>>> v(num) = -rho*HxdHy
>>>>
>>>> col(MatStencil_i,num) = i
>>>>
>>>> col(MatStencil_j,num) = j-1
>>>>
>>>> num = num + 1
>>>>
>>>> end if
>>>>
>>>> if (i/=0) then
>>>>
>>>> v(num) = -rho*HydHx
>>>>
>>>> col(MatStencil_i,num) = i-1
>>>>
>>>> col(MatStencil_j,num) = j
>>>>
>>>> num = num + 1
>>>>
>>>> end if
>>>>
>>>> if (i/=mx-1) then
>>>>
>>>> v(num) = -rho*HydHx
>>>>
>>>> col(MatStencil_i,num) = i+1
>>>>
>>>> col(MatStencil_j,num) = j
>>>>
>>>> num = num + 1
>>>>
>>>> end if
>>>>
>>>> if (j/=my-1) then
>>>>
>>>> v(num) = -rho*HxdHy
>>>>
>>>> col(MatStencil_i,num) = i
>>>>
>>>> col(MatStencil_j,num) = j+1
>>>>
>>>> num = num + 1
>>>>
>>>> end if
>>>>
>>>> v(num) = ((num-1)/2.0)*rho*(HxdHy + HydHx)
>>>>
>>>> print *, v
>>>>
>>>> col(MatStencil_i,num) = i
>>>>
>>>> col(MatStencil_j,num) = j
>>>>
>>>> !num = num + 1
>>>>
>>>> call
>>>> MatSetValuesStencil(jac,i1,row,num,col,v,INSERT_VALUES,ierr)
>>>>
>>>> I do not get any more out of range error. However,my ans is still
>>>> different from that of ex29 in C.
>>>>
>>>
>>> This is very simple. You have an error in your code. Checking it is
>>> very simple: run the code and
>>> break in MatSetValues(). Make sure ex29 makes calls with exactly the
>>> same indices as your ex29f.
>>>
>>> Matt
>>>
>>>
>>>> Yours sincerely,
>>>>
>>>> TAY wee-beng
>>>>
>>>
>>> --
>>> What most experimenters take for granted before they begin their
>>> experiments is infinitely more interesting than any results to which their
>>> experiments lead.
>>> -- Norbert Wiener
>>>
>>>
>>
>>
>> --
>> What most experimenters take for granted before they begin their
>> experiments is infinitely more interesting than any results to which their
>> experiments lead.
>> -- Norbert Wiener
>>
>>
>
>
> --
> What most experimenters take for granted before they begin their
> experiments is infinitely more interesting than any results to which their
> experiments lead.
> -- Norbert Wiener
>
>
--
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120504/6320fe37/attachment-0001.htm>
More information about the petsc-users
mailing list