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Problem resolved.<br>
<br>
As I suspected the problem was mine. My parallel runs were being
performed using input files that has a lower precision in the input<br>
data than those being used in my serial runs.<br>
<br>
-sanjay<br>
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<div class="moz-cite-prefix">On 5/15/19 7:25 AM, Mark Adams wrote:<br>
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cite="mid:CADOhEh7aP5Ag1CD5Wis=SrNneGnn+Yff5MuLHx8TzRmGyWqFZQ@mail.gmail.com">
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<div dir="ltr">This thread suggests that I was at least not wrong
in assuming that trailing 0s should be printed by printf
(although I did not trace the code down to printf)<br>
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<div><a
href="https://stackoverflow.com/questions/277772/avoid-trailing-zeroes-in-printf"
moz-do-not-send="true">https://stackoverflow.com/questions/277772/avoid-trailing-zeroes-in-printf</a><br>
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<div>Maybe Sanjay's machines printf cuts off trailing 0s.</div>
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<div dir="ltr" class="gmail_attr">On Wed, May 15, 2019 at 10:06
AM Smith, Barry F. <<a href="mailto:bsmith@mcs.anl.gov"
moz-do-not-send="true">bsmith@mcs.anl.gov</a>> wrote:<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
The 10-20% in seven digits are presumably printed
accurately; it is presumably simply the case that the rest of
the digits would be zero and hence are not printed. <br>
<br>
> On May 15, 2019, at 8:59 AM, Mark Adams via petsc-users
<<a href="mailto:petsc-users@mcs.anl.gov" target="_blank"
moz-do-not-send="true">petsc-users@mcs.anl.gov</a>>
wrote:<br>
> <br>
> You are seeing half precision (like 7 digits) in 10-20%
of the entries and full in the rest.<br>
> <br>
> Someone will probably chime in who knows about this but I
can see where a serial matrix is printed in ASCII Matlab in
MatView_SeqAIJ_ASCII in src/mat/impls/aij/seq/aij.c. <br>
> <br>
> I think this line is operative and is should clearly
work:<br>
> <br>
> ierr = PetscViewerASCIIPrintf(viewer,"%D %D
%18.16e\n",i+1,a->j[j]+1,(double)a->a[j]);CHKERRQ(ierr);<br>
> <br>
> Could you run in serial (this code could very well be
used for MPI Mats also) with Matlab/ASCII to verify that you
have this problem. And you could modify this print statement
and remake PETSc, if that's easy, to verify that this code is
operative.<br>
> <br>
> I think %18.16e should print 16 digits even if they are
0s ...<br>
> <br>
> <br>
> On Tue, May 14, 2019 at 8:34 PM Sanjay Govindjee <<a
href="mailto:s_g@berkeley.edu" target="_blank"
moz-do-not-send="true">s_g@berkeley.edu</a>> wrote:<br>
> I'm seeing half precision on at least 10 to 20% of the
entries :(<br>
> Knowing I should see full precision, I will dig deeper.<br>
> <br>
> -sanjay<br>
> On 5/14/19 5:22 PM, Mark Adams wrote:<br>
>> I would hope you get full precision. How many digits
are you seeing?<br>
>> <br>
>> On Tue, May 14, 2019 at 7:15 PM Sanjay Govindjee via
petsc-users <<a href="mailto:petsc-users@mcs.anl.gov"
target="_blank" moz-do-not-send="true">petsc-users@mcs.anl.gov</a>>
wrote:<br>
>> I am using the following bit of code to debug a
matrix. What is the <br>
>> expected precision of the numbers that I will find in
my ASCII file?<br>
>> As far as I can tell it is not the full double
precision that I was <br>
>> expecting.<br>
>> <br>
>> call
PetscViewerASCIIOpen(PETSC_COMM_WORLD, <br>
>> tangview,K_view, ierr)<br>
>> call PetscViewerSetFormat(K_view, <br>
>> PETSC_VIEWER_ASCII_MATLAB, ierr)<br>
>> call MatView (Kmat,
K_view, ierr)<br>
>> <br>
>> -sanjay<br>
>> <br>
> <br>
<br>
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