<div dir="ltr">I set the rigid body null vectors but PETSc errors out that these are not orthogonal. Is there a canned routine in PETSc to orthogonalize a bunch of Vecs?<div><br></div>





<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: Invalid argument</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: Vector 0 must be orthogonal to vector 2, inner product is 0.612391</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: See <a href="https://urldefense.us/v3/__https://petsc.org/release/faq/__;!!G_uCfscf7eWS!e0btVnW2NyDoumIgYMZpmOJ8Vvkh18HjVCEY3LyPW9fAsr4jD7MqRxxBLgh-q49bw3jvM0FZc2A_s2U6RxXpfK06Dg$">https://petsc.org/release/faq/</a> for trouble shooting.</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: Petsc Release Version 3.17.5, unknown<span class="gmail-Apple-converted-space"> </span></span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: ./acoustic_streaming_hier_integrator_2d on a darwin-dbg named APSB-MacBook-Pro-16.local by amneetb Mon Nov<span class="gmail-Apple-converted-space">  </span>4 18:01:09 2024</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: Configure options --CC=mpicc --CXX=mpicxx --FC=mpif90 --PETSC_ARCH=darwin-dbg --with-debugging=1 --download-hypre=1 --with-x=0 -download-mumps -download-scalapack -download-parmetis -download-metis -download-ptscotch</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: #1 MatNullSpaceCreate() at /Users/amneetb/Softwares/PETSc-Gitlab/PETSc/src/mat/interface/matnull.c:271</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">[0]PETSC ERROR: #2 resetMatNearNullspace() at ../../../IBAMR/ibtk/lib/../src/solvers/impls/PETScKrylovLinearSolver.cpp:697</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">P=00000:Program abort called in file ``../../../IBAMR/ibtk/lib/../src/solvers/impls/PETScKrylovLinearSolver.cpp'' at line 697</span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">P=00000:ERROR MESSAGE:<span class="gmail-Apple-converted-space"> </span></span></p>
<p class="gmail-p1" style="margin:0px;font-variant-numeric:normal;font-variant-east-asian:normal;font-variant-alternates:normal;font-size-adjust:none;font-kerning:auto;font-feature-settings:normal;font-stretch:normal;font-size:18px;line-height:normal;font-family:Monaco;color:rgb(242,242,242);background-color:rgba(0,0,0,0.85)"><span class="gmail-s1" style="font-variant-ligatures:no-common-ligatures">P=00000:</span></p>
<div><span style="font-variant-ligatures:no-common-ligatures;background-color:rgba(0,0,0,0.85);color:rgb(242,242,242);font-family:Monaco;font-size:18px">Abort trap: 6</span> </div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 4, 2024 at 10:11 AM Jed Brown <<a href="mailto:jed@jedbrown.org">jed@jedbrown.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Unless the problem is entirely floating (the true null space is all six rigid body modes), then they will be different, so yes, you'll typically have two MatNullSpace objects.<br>
<br>
Amneet Bhalla <<a href="mailto:mail2amneet@gmail.com" target="_blank">mail2amneet@gmail.com</a>> writes:<br>
<br>
> Hi Jed,<br>
><br>
> Do I need to create two separate MattNullSpace objects if I want to use<br>
> both MatSetNullSpace() and MatSetNearNullSpace()?<br>
><br>
> Thanks,<br>
><br>
><br>
> On Thu, Oct 31, 2024 at 8:18 AM Jed Brown <<a href="mailto:jed@jedbrown.org" target="_blank">jed@jedbrown.org</a>> wrote:<br>
><br>
>> Pierre Jolivet <<a href="mailto:pierre@joliv.et" target="_blank">pierre@joliv.et</a>> writes:<br>
>><br>
>> >> On 31 Oct 2024, at 2:47 PM, Mark Adams <<a href="mailto:mfadams@lbl.gov" target="_blank">mfadams@lbl.gov</a>> wrote:<br>
>> >><br>
>> >> Interesting. I have seen hypre do fine on elasticity, but do you know<br>
>> if boomeramg (classical) uses these vectors or is there a smoothed<br>
>> aggregation solver in hypre?<br>
>> ><br>
>> > I’m not sure it is precisely “standard” smoothed aggregation, see bottom<br>
>> paragraph of<br>
>> <a href="https://urldefense.us/v3/__https://hypre.readthedocs.io/en/latest/solvers-boomeramg.html*amg-for-systems-of-pdes__;Iw!!G_uCfscf7eWS!fdj4AzKhAcDmM1x_ZQ8gxqWeX6BAKY9urnvATMpT7hC8lw77ak7tqxqXGIX3PMg2wYA5PGu7EzyCW0yzixutBg$" rel="noreferrer" target="_blank">https://urldefense.us/v3/__https://hypre.readthedocs.io/en/latest/solvers-boomeramg.html*amg-for-systems-of-pdes__;Iw!!G_uCfscf7eWS!fdj4AzKhAcDmM1x_ZQ8gxqWeX6BAKY9urnvATMpT7hC8lw77ak7tqxqXGIX3PMg2wYA5PGu7EzyCW0yzixutBg$</a><br>
>> > I’ve never made it to work, but I know some do.<br>
>> > A while back, Stefano gave me this pointer as well:<br>
>> <a href="https://urldefense.us/v3/__https://github.com/mfem/mfem/blob/17955e114020af340e9a06a66ebef43e05012d9c/linalg/hypre.cpp*L5245__;Iw!!G_uCfscf7eWS!fdj4AzKhAcDmM1x_ZQ8gxqWeX6BAKY9urnvATMpT7hC8lw77ak7tqxqXGIX3PMg2wYA5PGu7EzyCW0wVEi33Pw$" rel="noreferrer" target="_blank">https://urldefense.us/v3/__https://github.com/mfem/mfem/blob/17955e114020af340e9a06a66ebef43e05012d9c/linalg/hypre.cpp*L5245__;Iw!!G_uCfscf7eWS!fdj4AzKhAcDmM1x_ZQ8gxqWeX6BAKY9urnvATMpT7hC8lw77ak7tqxqXGIX3PMg2wYA5PGu7EzyCW0wVEi33Pw$</a><br>
>><br>
>> It's still classical AMG, and in my experience, struggles on very thin<br>
>> structures (e.g., aspect ratio 1000 cantilever beams) when compared to SA.<br>
>> However, it can be quite competitive for many structures. I found that the<br>
>> "MFEM elasticity suite", which is based on Baker et al 2010, gave rather<br>
>> poor results. This is a configuration that works on GPUs and gives good<br>
>> convergence and performance for elasticity:<br>
>><br>
>><br>
>> <a href="https://urldefense.us/v3/__https://github.com/hypre-space/hypre/issues/601*issuecomment-1069426997__;Iw!!G_uCfscf7eWS!arUVBVKKcYs1M5OhNqqRZl2b2o0NIUkG7fV_22qBbg-ssHhhHazhkpMbYNjCOTN66Sfbk-VZilfox9bxDf0$" rel="noreferrer" target="_blank">https://urldefense.us/v3/__https://github.com/hypre-space/hypre/issues/601*issuecomment-1069426997__;Iw!!G_uCfscf7eWS!arUVBVKKcYs1M5OhNqqRZl2b2o0NIUkG7fV_22qBbg-ssHhhHazhkpMbYNjCOTN66Sfbk-VZilfox9bxDf0$</a><br>
>><br>
>> In the above issue, I was only using BoomerAMG as a coarse level for p-MG<br>
>> so all the options have a `-mg_coarse_` prefix; here are those options<br>
>> without the prefix:<br>
>><br>
>> -pc_hypre_boomeramg_coarsen_type pmis<br>
>> -pc_hypre_boomeramg_interp_type ext+i<br>
>> -pc_hypre_boomeramg_no_CF<br>
>> -pc_hypre_boomeramg_P_max 6<br>
>> -pc_hypre_boomeramg_print_statistics 1<br>
>> -pc_hypre_boomeramg_relax_type_down Chebyshev<br>
>> -pc_hypre_boomeramg_relax_type_up Chebyshev<br>
>> -pc_hypre_boomeramg_strong_threshold 0.5<br>
>> -pc_type hypre<br>
>><br>
><br>
><br>
> -- <br>
> --Amneet<br>
</blockquote></div><br clear="all"><div><br></div><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div>--Amneet <br><br></div><div><br></div><div><br></div></div></div>