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<H1>SVDComputeRelativeError</H1>
Computes the relative error bound associated with the i-th singular triplet.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcsvd.h"
PetscErrorCode SVDComputeRelativeError(SVD svd,PetscInt i,PetscReal *error)
</PRE>
Collective on <A HREF="../SVD/SVD.html#SVD">SVD</A>
<P>
<H3><FONT COLOR="#883300">Input Parameter</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>svd </B></TD><TD> - the singular value solver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>i </B></TD><TD> - the solution index
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Output Parameter</FONT></H3>
<DT><B>error </B> - the relative error bound, computed as sqrt(n1^2+n2^2)/sigma
where n1 = ||A*v-sigma*u||_2 , n2 = ||A^T*u-sigma*v||_2 , sigma is the singular value,
u and v are the left and right singular vectors.
If sigma is too small the relative error is computed as sqrt(n1^2+n2^2).
<br>
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../SVD/SVDSolve.html#SVDSolve">SVDSolve</A>(), <A HREF="../SVD/SVDComputeResidualNorms.html#SVDComputeResidualNorms">SVDComputeResidualNorms</A>()
<BR><P><B><FONT COLOR="#883300">Location: </FONT></B><A HREF="../../../src/svd/interface/svdsolve.c.html#SVDComputeRelativeError">src/svd/interface/svdsolve.c</A>
<BR><A HREF="./index.html">Index of all SVD routines</A>
<BR><A HREF="../../index.html">Table of Contents for all manual pages</A>
<BR><A HREF="../singleindex.html">Index of all manual pages</A>
<P><H3><FONT COLOR="#883300">Examples</FONT></H3>
<A HREF="../../../src/svd/examples/tutorials/ex15.c.html">src/svd/examples/tutorials/ex15.c.html</A><BR>
<A HREF="../../../src/svd/examples/tutorials/ex15f.F.html">src/svd/examples/tutorials/ex15f.F.html</A><BR>
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