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On 4/5/2012 3:05 PM, Matthew Knepley wrote:
<blockquote
cite="mid:CAMYG4GmuXKfzo8MMMDU=yPefrF-jeA8STc04+D3E56foCEXiOA@mail.gmail.com"
type="cite">
<div class="gmail_extra">On Fri, May 4, 2012 at 8:59 AM, TAY
wee-beng <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:zonexo@gmail.com" target="_blank">zonexo@gmail.com</a>></span>
wrote:<br>
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"> <br>
Hi,<br>
<br>
Is there anything else I can try to get it working right?<br>
</div>
</blockquote>
<div><br>
</div>
<div>The MatGetNullSpaceRemove() is missing.</div>
</div>
</div>
</blockquote>
Where should I add MatGetNullSpaceRemove and what are its syntax? I
googled but there's no results.<br>
<br>
Thanks.<br>
<blockquote
cite="mid:CAMYG4GmuXKfzo8MMMDU=yPefrF-jeA8STc04+D3E56foCEXiOA@mail.gmail.com"
type="cite">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<div> Matt</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"> Thanks！<br>
<br>
<br>
On 2/5/2012 10:11 PM, Matthew Knepley wrote:
<blockquote type="cite">
<div class="gmail_extra">On Wed, May 2, 2012 at 1:55 PM,
TAY wee-beng <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:zonexo@gmail.com" target="_blank">zonexo@gmail.com</a>></span>
wrote:<br>
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"> Hi,<br>
<br>
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?<br>
</div>
</blockquote>
<div><br>
</div>
<div>Did you set the null space for the matrix when
you have Neumann conditions?</div>
</div>
</div>
</blockquote>
Yes, for the matrix, I set as:<br>
<br>
call
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL_OBJECT,nullspace,ierr)<br>
<br>
call MatSetNullSpace(jac,nullspace,ierr)<br>
<br>
call MatNullSpaceDestroy(nullspace,ierr)<br>
<br>
for the Vec, <br>
<br>
call
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL_OBJECT,nullspace,ierr)<br>
<br>
<b>!call
MatNullSpaceRemove(nullspace,b,PETSC_NULL,ierr)</b><br>
<br>
call MatNullSpaceDestroy(nullspace,ierr)<br>
<br>
MatNullSpaceRemove was comment out because there's error
during linking<br>
<br>
<br>
<blockquote type="cite">
<div class="gmail_extra">
<div class="gmail_quote">
<div><br>
</div>
<div> Matt</div>
<div> </div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000"> Thanks!<br>
<br>
Fortran:<br>
<br>
Matrix Object: 1 MPI processes<br>
type: seqaij<br>
row 0: (0, 2) (1, -1) (3, -1)<br>
row 1: (0, -1) (1, 3) (2, -1) (4, -1)<br>
row 2: (1, -1) (2, 2) (5, -1)<br>
row 3: (0, -1) (3, 3) (4, -1) (6, -1)<br>
row 4: (1, -1) (3, -1) (4, 4) (5, -1) (7,
-1)<br>
row 5: (2, -1) (4, -1) (5, 3) (8, -1)<br>
row 6: (3, -1) (6, 2) (7, -1)<br>
row 7: (4, -1) (6, -1) (7, 3) (8, -1)<br>
row 8: (5, -1) (7, -1) (8, 2)<br>
Vector Object:Vec_0000000084000000_0 1 MPI
processes<br>
type: mpi<br>
Process [0]<br>
0.25<br>
0.0205213<br>
1.135e-005<br>
0.0205213<br>
0.00168449<br>
9.31663e-007<br>
1.135e-005<br>
9.31663e-007<br>
5.15289e-010<br>
Vector Object:Vec_0000000084000000_1 1 MPI
processes<br>
type: mpi<br>
Process [0]<br>
0.14924<br>
0.0242397<br>
-0.0260347<br>
0.0242397<br>
-0.0256192<br>
-0.0400102<br>
-0.0260347<br>
-0.0400102<br>
-0.0400102<br>
Press any key to continue . . .<br>
<br>
C:<br>
<br>
Matrix Object: 1 MPI processes<br>
type: seqaij<br>
row 0: (0, 2) (1, -1) (3, -1) <br>
row 1: (0, -1) (1, 3) (2, -1) (4, -1) <br>
row 2: (1, -1) (2, 2) (5, -1) <br>
row 3: (0, -1) (3, 3) (4, -1) (6, -1) <br>
row 4: (1, -1) (3, -1) (4, 4) (5, -1) (7,
-1) <br>
row 5: (2, -1) (4, -1) (5, 3) (8, -1) <br>
row 6: (3, -1) (6, 2) (7, -1) <br>
row 7: (4, -1) (6, -1) (7, 3) (8, -1) <br>
row 8: (5, -1) (7, -1) (8, 2) <br>
Vector Object:Vec_0x1d3b000_0 1 MPI processes<br>
type: mpi<br>
Process [0]<br>
0.25<br>
0.0205212<br>
1.135e-05<br>
0.0205212<br>
0.00168449<br>
9.31663e-07<br>
1.135e-05<br>
9.31663e-07<br>
5.15288e-10<br>
Vector Object:Vec_0x1d3b000_1 1 MPI processes<br>
type: mpi<br>
Process [0]<br>
0.139311<br>
0.0305751<br>
-0.0220633<br>
0.0305751<br>
-0.0135158<br>
-0.042185<br>
-0.0220633<br>
-0.042185<br>
-0.058449<br>
<br>
<br>
<br>
<pre cols="72">Yours sincerely,
TAY wee-beng</pre>
<br>
On 1/5/2012 11:54 PM, Matthew Knepley wrote:
<blockquote type="cite">
<div class="gmail_extra">On Tue, May 1, 2012
at 5:48 PM, TAY wee-beng <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:zonexo@gmail.com"
target="_blank">zonexo@gmail.com</a>></span>
wrote:<br>
<div class="gmail_quote">
<blockquote class="gmail_quote"
style="margin:0 0 0 .8ex;border-left:1px
#ccc solid;padding-left:1ex"> Hi,<br>
<br>
Do you mean my method is wrong?<br>
<br>
I am following the template of ex22f,<br>
<br>
where the variables are declared as :<br>
<br>
PetscScalar v(5)<br>
<br>
MatStencil row(4),col(4,5)<br>
<br>
Hence,<br>
<br>
for the neumann BC<br>
<br>
num = 1<br>
<br>
if (j/=0) then<br>
<br>
v(num) = -rho*HxdHy<br>
<br>
col(MatStencil_i,num)
= i<br>
<br>
col(MatStencil_j,num)
= j-1<br>
<br>
num = num + 1<br>
<br>
end if<br>
<br>
if (i/=0) then<br>
<br>
v(num) = -rho*HydHx<br>
<br>
col(MatStencil_i,num)
= i-1<br>
<br>
col(MatStencil_j,num)
= j<br>
<br>
num = num + 1<br>
<br>
end if<br>
<br>
if (i/=mx-1) then<br>
<br>
v(num) = -rho*HydHx<br>
<br>
col(MatStencil_i,num)
= i+1<br>
<br>
col(MatStencil_j,num)
= j<br>
<br>
num = num + 1<br>
<br>
end if<br>
<br>
if (j/=my-1) then<br>
<br>
v(num) = -rho*HxdHy<br>
<br>
col(MatStencil_i,num)
= i<br>
<br>
col(MatStencil_j,num)
= j+1<br>
<br>
num = num + 1<br>
<br>
end if<br>
<br>
v(num) =
((num-1)/2.0)*rho*(HxdHy + HydHx)<br>
<br>
print *, v<br>
<br>
col(MatStencil_i,num) = i<br>
<br>
col(MatStencil_j,num) = j<br>
<br>
!num = num + 1<br>
<br>
call
MatSetValuesStencil(jac,i1,row,num,col,v,INSERT_VALUES,ierr)<br>
<br>
I do not get any more out of range
error. However,my ans is still different
from that of ex29 in C.<br>
</blockquote>
<div><br>
</div>
<div>This is very simple. You have an
error in your code. Checking it is very
simple: run the code and</div>
<div>break in MatSetValues(). Make sure
ex29 makes calls with exactly the same
indices as your ex29f.</div>
<div><br>
</div>
<div> Matt</div>
<div> </div>
<blockquote class="gmail_quote"
style="margin:0 0 0 .8ex;border-left:1px
#ccc solid;padding-left:1ex"> Yours
sincerely,<br>
<br>
TAY wee-beng<br>
</blockquote>
</div>
<div><br>
<span class="HOEnZb"><font color="#888888">
<span><font color="#888888"> </font></span></font></span></div>
<span class="HOEnZb"><font color="#888888">
<span><font color="#888888"> -- <br>
What most experimenters take for
granted before they begin their
experiments is infinitely more
interesting than any results to
which their experiments lead.<br>
-- Norbert Wiener<br>
</font></span></font></span></div>
<span class="HOEnZb"><font color="#888888"> </font></span></blockquote>
<span class="HOEnZb"><font color="#888888"> </font></span></div>
<span class="HOEnZb"><font color="#888888"> </font></span></blockquote>
<span class="HOEnZb"><font color="#888888"> </font></span></div>
<span class="HOEnZb"><font color="#888888"> <br>
<br clear="all">
<div><br>
</div>
-- <br>
What most experimenters take for granted before
they begin their experiments is infinitely more
interesting than any results to which their
experiments lead.<br>
-- Norbert Wiener<br>
</font></span></div>
</blockquote>
</div>
</blockquote>
</div>
<br>
<br clear="all">
<div><br>
</div>
-- <br>
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to
which their experiments lead.<br>
-- Norbert Wiener<br>
</div>
</blockquote>
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