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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Thank you. It worked!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Karthik.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">Pierre Jolivet <pierre@joliv.et><br>
<b>Date: </b>Friday, 18 November 2022 at 13:56<br>
<b>To: </b>Chockalingam, Karthikeyan (STFC,DL,HC) <karthikeyan.chockalingam@stfc.ac.uk><br>
<b>Cc: </b>petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov><br>
<b>Subject: </b>Re: [petsc-users] PetscOptionsSetValue syntax<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><br>
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<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">On 18 Nov 2022, at 2:47 PM, Karthikeyan Chockalingam - STFC UKRI <karthikeyan.chockalingam@stfc.ac.uk> wrote:<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Thank you. I added</span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:black"> ierr =
</span><span style="font-size:9.0pt;font-family:Menlo;color:#6C36A9">KSPSetFromOptions</span><span style="font-size:9.0pt;font-family:Menlo;color:black">(ksp);
</span><span style="font-size:9.0pt;font-family:Menlo;color:#643820">CHKERRQ</span><span style="font-size:9.0pt;font-family:Menlo;color:black">(ierr);</span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">before </span><span class="s1">PetscOptionsSetValue
</span><span style="mso-fareast-language:EN-US">but still I don’t see the ksp iterations or any other info flags I set.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I am not passing anything via the command line and believe
</span><span class="s1">PetscOptionsSetValue </span><span style="mso-fareast-language:EN-US">would set the flags.</span><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">If you call KSPSetFromOptions() before you set any options, there is nothing to set.<o:p></o:p></p>
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<p class="MsoNormal">Usually, you want to delay calling that function up until you are done setting options.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal">Pierre<o:p></o:p></p>
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<p class="MsoNormal"><br>
<br>
<o:p></o:p></p>
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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Best,</span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Karthik.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"> </span><o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">Pierre Jolivet <pierre@joliv.et><br>
<b>Date: </b>Friday, 18 November 2022 at 13:36<br>
<b>To: </b>Chockalingam, Karthikeyan (STFC,DL,HC) <karthikeyan.chockalingam@stfc.ac.uk><br>
<b>Cc: </b>petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov><br>
<b>Subject: </b>Re: [petsc-users] PetscOptionsSetValue syntax</span><o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">On 18 Nov 2022, at 2:32 PM, Karthikeyan Chockalingam - STFC UKRI via petsc-users <petsc-users@mcs.anl.gov> wrote:<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">I would like to move from code to using options. <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:#3900A0"> KSP</span><span style="font-size:9.0pt;font-family:Menlo;color:black"> ksp;</span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:black"> </span><span style="font-size:9.0pt;font-family:Menlo;color:#3900A0">PC</span><span style="font-size:9.0pt;font-family:Menlo;color:black">
pc;</span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:#6C36A9"> KSPCreate(PETSC_COMM_WORLD, &ksp);</span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:black"> </span><span style="font-size:9.0pt;font-family:Menlo;color:#6C36A9">KSPSetOperators</span><span style="font-size:9.0pt;font-family:Menlo;color:black">(ksp,
A, A);</span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:black"> </span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="color:black">I tried using PetscOptionsSetValue as below</span><o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:9.0pt;font-family:Menlo;color:black"> </span><o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>ierr = <span class="s1">
PetscOptionsSetValue</span>(<span class="s2"><b>NULL</b></span>,<span class="s3">"-ksp_type"</span>,
<span class="s3">"cg"</span>); <span class="s4">CHKERRQ</span>(ierr);<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>ierr = <span class="s1">
PetscOptionsSetValue</span>(<span class="s2"><b>NULL</b></span>,<span class="s3">"-pc_type"</span>,
<span class="s3">"jacobi"</span>); <span class="s4">CHKERRQ</span>(ierr);<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>ierr = <span class="s1">
PetscOptionsSetValue</span>(<span class="s2"><b>NULL</b></span>, <span class="s3">
"-ksp_monitor"</span>, <span class="s2"><b>NULL</b></span>);<span class="s4">CHKERRQ</span>(ierr);<o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>ierr = <span class="s1">
PetscOptionsSetValue</span>(<span class="s2"><b>NULL</b></span>, <span class="s3">
"-ksp_view"</span>, <span class="s2"><b>NULL</b></span>);<span class="s4">CHKERRQ</span>(ierr);<o:p></o:p></p>
<p class="p2"><span class="apple-converted-space"> </span><span class="s5">ierr =
</span><span class="s1">PetscOptionsSetValue</span><span class="s5">(</span><span class="s2"><b>NULL</b></span><span class="s5">,
</span>"-ksp_monitor_true_residual"<span class="s5">, </span><span class="s2"><b>NULL</b></span><span class="s5">);</span><span class="s4">CHKERRQ</span><span class="s5">(ierr);</span><o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span>ierr = <span class="s1">
PetscOptionsSetValue</span>(<span class="s2"><b>NULL</b></span>, <span class="s3">
"-ksp_converged_reason"</span>, <span class="s2"><b>NULL</b></span>);<span class="s4">CHKERRQ</span>(ierr);<o:p></o:p></p>
<p class="p1"> <o:p></o:p></p>
<p class="p1"><span class="apple-converted-space"> </span><span class="s1">KSPSolve</span>(ksp, b, x);<o:p></o:p></p>
<p class="MsoNormal" style="background:white"><span style="font-size:10.0pt;color:black"> </span><o:p></o:p></p>
<p class="MsoNormal">But I believe none of the string flags where picked up by PETSc. What am I missing?<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">KSPSetFromOptions()<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Thanks,<o:p></o:p></p>
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<p class="MsoNormal">Pierre<o:p></o:p></p>
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<p class="MsoNormal"><br>
<br>
<br>
<o:p></o:p></p>
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<p class="MsoNormal">Thank you for your help.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Kind regards,<o:p></o:p></p>
<p class="MsoNormal">Karthik.<o:p></o:p></p>
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