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    <p>Hi there,</p>
    <p>I am using -ts_type pseudo to find steady solutions of the
      Euler/NS PDEs.</p>
    <p>It looks like FormRHSFunction is called twice with the exactly
      same value of the dependent variable (u)</p>
    <p>before invoking TSRHSJacobianFn and then solving the linear
      system with KSP (u is then updated)<br>
    </p>
    <p>
      <blockquote type="cite"><span style="font-family:monospace"><span
            style="color:#000000;background-color:#ffffff;">1 TS dt
            0.141197 time 0.141197</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            FormRHSFunction; ||u|| =    60.489405479528003
                   463.15635675129079        62.813532026019146
                   5.9789502719351155    </span><span
            style="color:#000000;background-color:#ffffff;"> </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            FormRHSFunction; ||u|| =    60.489405479528003
                   463.15635675129079</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">62.813532026019146</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">5.9789502719351155</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            TSRHSJacobianFn with ||u|| =    60.489405479528003
                   463.15635675129079        62.813532026019146
                   5.9789502719351155</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;">
                 Linear solve converged due to CONVERGED_RTOL iterations
            9</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            FormRHSFunction; ||u|| =    60.489405476878737</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">463.15635675602186</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">62.813532031616965</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">5.9789502710519811</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;">2 TS dt
            0.155917 time 0.297115</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            FormRHSFunction; ||u|| =    60.489405476878737</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">463.15635675602186</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">62.813532031616965</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">5.9789502710519811</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            FormRHSFunction; ||u|| =    60.489405476878737</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">463.15635675602186</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">62.813532031616965</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">5.9789502710519811</span><span
            style="color:#000000;background-color:#ffffff;">
          </span><br>
          <span style="color:#000000;background-color:#ffffff;"> Calling
            TSRHSJacobianFn with ||u|| =    60.489405476878737</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">463.15635675602186</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">62.813532031616965</span><span
            style="color:#000000;background-color:#ffffff;">        </span><span
            style="color:#000000;background-color:#ffffff;">5.9789502710519811</span><br>
          <span style="color:#000000;background-color:#ffffff;">
          </span><br>
        </span></blockquote>
      Why is it so? Am I possibly misusing (or missing) some options? <br>
    </p>
    <p>My .petscrc file is attached.</p>
    <p>Thank you,</p>
    <p>Aldo<br>
    </p>
    <pre class="moz-signature" cols="72">-- 
Dr. Aldo Bonfiglioli
Associate professor of Fluid Mechanics
Dipartimento di Ingegneria
Universita' della Basilicata
V.le dell'Ateneo Lucano, 10 85100 Potenza ITALY
tel:+39.0971.205203 fax:+39.0971.205215
web: <a class="moz-txt-link-freetext" href="https://urldefense.us/v3/__http://docenti.unibas.it/site/home/docente.html?m=002423__;!!G_uCfscf7eWS!ci_aySHdF2Qx_B-37IOzELFDtcQRthJ2NItK-JNbfXB0M2_21B_z97WIfjxZUyKCVRRhd1mzL6b-rnCed_i8LLA56JvFdz7JBrw$">http://docenti.unibas.it/site/home/docente.html?m=002423</a></pre>
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