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<div id="version" align=right><b>slepc-3.23.1 2025-05-01</b></div>
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<H1>DSCond</H1>
Compute the condition number.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcds.h"
<A HREF="https://petsc.org/release/manualpages/Sys/PetscErrorCode.html#PetscErrorCode">PetscErrorCode</A> <A HREF="../DS/DSCond.html#DSCond">DSCond</A>(<A HREF="../DS/DS.html#DS">DS</A> ds,<A HREF="https://petsc.org/release/manualpages/Sys/PetscReal.html#PetscReal">PetscReal</A> *cond)
</PRE>
Logically Collective
<P>
<H3><FONT COLOR="#883300">Input Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>ds </B></TD><TD> - the direct solver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>cond </B></TD><TD> - the computed condition number
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
In standard eigenvalue problems, returns the inf-norm condition number of the first
matrix, computed as cond(A) = norm(A)*norm(inv(A)).
<P>
In GSVD problems, returns the maximum of cond(A) and cond(B), where cond(.) is
computed as the ratio of the largest and smallest singular values.
<P>
Does not take into account the extra row.
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../DS/DSSolve.html#DSSolve">DSSolve</A>(), <A HREF="../DS/DSSetExtraRow.html#DSSetExtraRow">DSSetExtraRow</A>()
<BR><P><B></B><H3><FONT COLOR="#883300">Level</FONT></H3>advanced<BR>
<H3><FONT COLOR="#883300">Location</FONT></H3>
</B><A HREF="../../../src/sys/classes/ds/interface/dsops.c.html#DSCond">src/sys/classes/ds/interface/dsops.c</A>
<BR><BR><A HREF="./index.html">Index of all DS routines</A>
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