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<p>We recently updated our installation of PETSC and SLEPC from an older version, and eigenvalue problems converging in the previous installation is not converging anymore (diagonalization never comes to an end). On using -info, the following message keeps
repeating during diagonalization:</p>
<p><br>
</p>
<p></p>
<div>[0] PCSetUp(): Leaving PC with identical preconditioner since operator is unchanged</div>
<div>[0] STMatSolve(): Linear solve iterations=1</div>
<div>[0] PCSetUp(): Leaving PC with identical preconditioner since operator is unchanged</div>
<div>[0] STMatSolve(): Linear solve iterations=1</div>
<div><b>[0] BV_SafeSqrt(): Zero norm, either the vector is zero or a semi-inner product is being used</b></div>
<div>[0] PCSetUp(): Leaving PC with identical preconditioner since operator is unchanged</div>
<div>[0] STMatSolve(): Linear solve iterations=1</div>
<div>[0] PCSetUp(): Leaving PC with identical preconditioner since operator is unchanged</div>
<div>[0] STMatSolve(): Linear solve iterations=1</div>
<div><br>
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As can be seen, iteration number remains 1. The issue gets resolved with a smaller sized matrix. Currently I am using a 10648 x <span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">10648
matrix, and PETSC is configured for complex values.</span>
<p></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">What changes do I have to make to make my codes work in the new
installation? This seems to be a version specific issue.</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;"><br>
</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">Thanks,</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">Sidd</span></p>
<p><span style="font-family: Calibri, Helvetica, sans-serif, EmojiFont, "Apple Color Emoji", "Segoe UI Emoji", NotoColorEmoji, "Segoe UI Symbol", "Android Emoji", EmojiSymbols; font-size: 16px;">WPI</span></p>
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