<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:#954F72;
text-decoration:underline;}
p.msonormal0, li.msonormal0, div.msonormal0
{mso-style-name:msonormal;
mso-margin-top-alt:auto;
margin-right:0cm;
mso-margin-bottom-alt:auto;
margin-left:0cm;
font-size:12.0pt;
font-family:"Times New Roman",serif;}
span.apple-converted-space
{mso-style-name:apple-converted-space;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 70.85pt 70.85pt 70.85pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-US" link="#0563C1" vlink="#954F72">
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">In if this is a bug, I think the fix you proposed should also be applied to the destroy() method, as it does not clear the database either.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Alexandre.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<div>
<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm">
<p class="MsoNormal"><b><span lang="FR" style="font-size:11.0pt;font-family:"Calibri",sans-serif">De :</span></b><span lang="FR" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Pierre Jolivet <pierre@joliv.et>
<br>
<b>Envoyé :</b> lundi 27 octobre 2025 10:36<br>
<b>À :</b> SCOTTO Alexandre <alexandre.scotto@irt-saintexupery.com><br>
<b>Cc :</b> petsc-users@mcs.anl.gov<br>
<b>Objet :</b> Re: [petsc-users] Options database in petsc4py<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I would say this is a bug in petsc4py, the following diff should fix this.<o:p></o:p></p>
<div>
<p class="MsoNormal">I’m not sure why this if is there, as it’s perfectly valid to call PetscOptionsClear(NULL).<o:p></o:p></p>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">Pierre<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
<div>
<div>
<p class="MsoNormal">diff --git a/src/binding/petsc4py/src/petsc4py/PETSc/Options.pyx b/src/binding/petsc4py/src/petsc4py/PETSc/Options.pyx<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">index 4db3c52f022..8a923a6dd8e 100644<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">--- a/src/binding/petsc4py/src/petsc4py/PETSc/Options.pyx<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">+++ b/src/binding/petsc4py/src/petsc4py/PETSc/Options.pyx<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">@@ -90,7 +90,6 @@ cdef class Options:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> <o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> def clear(self) -> Self:<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> """Clear an options database."""<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal">- if self.opt == NULL: return<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> CHKERR(PetscOptionsClear(self.opt))<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"> return self<o:p></o:p></p>
</div>
<div>
<p class="MsoNormal"><br>
<br>
<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<p class="MsoNormal">On 27 Oct 2025, at 10:23 AM, SCOTTO Alexandre via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<o:p></o:p></p>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Dear PETSc Community,<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">In my developments, I am managing possibly several KSP solvers with options handled by the Options database. During my tests, I encountered the following behavior:<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Code</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">:<o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">options = PETSc.Options("ksp_")</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">options.setValue("atol", 7e-8)</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">options.view()</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver"> </span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">options.clear()</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">options.view()</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Output</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">:<o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">#PETSc Option Table entries:</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span lang="FR" style="font-size:11.0pt;font-family:"Courier New";background:silver">-ksp_atol 7e-08 # (source: code)</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">#End of PETSc Option Table entries</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver"> </span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">#PETSc Option Table entries:</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">-ksp_atol 7e-08 # (source: code)</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";background:silver">#End of PETSc Option Table entries</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New""> </span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">It seems that the<span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Courier New";background:silver">clear()</span><span class="apple-converted-space"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">method
does not really clear the Option database. To ensure that the several KSP I deal with are set with their own options (without getting options from a KSP previously set), the only way I found was to explicitly call the<span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Courier New";background:silver">delValue()</span><span class="apple-converted-space"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">method
for all the option keys passed:<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal" style="text-indent:-18.0pt"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">1.</span><span style="font-size:7.0pt"> <span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Iterate
over a dictionary of options and use<span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Courier New";background:silver">setValue(name, value)</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal" style="text-indent:-18.0pt"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">2.</span><span style="font-size:7.0pt"> <span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Set
the KSP with option database:<span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Courier New";background:silver">KSP.setFromOptions()</span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"><o:p></o:p></span></p>
</div>
<div style="margin-left:36.0pt">
<p class="MsoNormal" style="text-indent:-18.0pt"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">3.</span><span style="font-size:7.0pt"> <span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Iterate
over a the keys of the dictionary and<span class="apple-converted-space"> </span></span><span style="font-size:11.0pt;font-family:"Courier New"">use<span class="apple-converted-space"> </span><span style="background:silver">delValue(name)</span></span><span class="apple-converted-space"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> </span></span><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">to
effectively clear the option database.<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Does it seem normal to you, is there something I am missing out?<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> <o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Regards,<o:p></o:p></span></p>
</div>
<div>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">Alexandre Scotto.<o:p></o:p></span></p>
</div>
</div>
</blockquote>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</div>
</div>
</body>
</html>