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<div id="version" align=right><b>slepc-3.23.1 2025-05-01</b></div>
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<H1>SVDGetSingularTriplet</H1>
Gets the i-th triplet of the singular value decomposition as computed by <A HREF="../SVD/SVDSolve.html#SVDSolve">SVDSolve</A>(). The solution consists in the singular value and its left and right singular vectors.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcsvd.h"
<A HREF="https://petsc.org/release/manualpages/Sys/PetscErrorCode.html#PetscErrorCode">PetscErrorCode</A> <A HREF="../SVD/SVDGetSingularTriplet.html#SVDGetSingularTriplet">SVDGetSingularTriplet</A>(<A HREF="../SVD/SVD.html#SVD">SVD</A> svd,<A HREF="https://petsc.org/release/manualpages/Sys/PetscInt.html#PetscInt">PetscInt</A> i,<A HREF="https://petsc.org/release/manualpages/Sys/PetscReal.html#PetscReal">PetscReal</A> *sigma,<A HREF="https://petsc.org/release/manualpages/Vec/Vec.html#Vec">Vec</A> u,<A HREF="https://petsc.org/release/manualpages/Vec/Vec.html#Vec">Vec</A> v)
</PRE>
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>svd </B></TD><TD> - singular value solver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>i </B></TD><TD> - index of the solution
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Output Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>sigma </B></TD><TD> - singular value
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>u </B></TD><TD> - left singular vector
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>v </B></TD><TD> - right singular vector
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Note</FONT></H3>
Both u or v can be NULL if singular vectors are not required.
Otherwise, the caller must provide valid <A HREF="https://petsc.org/release/manualpages/Vec/Vec.html#Vec">Vec</A> objects, i.e.,
they must be created by the calling program with e.g. <A HREF="https://petsc.org/release/manualpages/Mat/MatCreateVecs.html#MatCreateVecs">MatCreateVecs</A>().
<P>
The index i should be a value between 0 and nconv-1 (see <A HREF="../SVD/SVDGetConverged.html#SVDGetConverged">SVDGetConverged</A>()).
Singular triplets are indexed according to the ordering criterion established
with <A HREF="../SVD/SVDSetWhichSingularTriplets.html#SVDSetWhichSingularTriplets">SVDSetWhichSingularTriplets</A>().
<P>
In the case of GSVD, the solution consists in three vectors u,v,x that are
returned as follows. Vector x is returned in the right singular vector
(argument v) and has length equal to the number of columns of A and B.
The other two vectors are returned stacked on top of each other [u;v] in
the left singular vector argument, with length equal to m+n (number of rows
of A plus number of rows of B).
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../SVD/SVDSolve.html#SVDSolve">SVDSolve</A>(), <A HREF="../SVD/SVDGetConverged.html#SVDGetConverged">SVDGetConverged</A>(), <A HREF="../SVD/SVDSetWhichSingularTriplets.html#SVDSetWhichSingularTriplets">SVDSetWhichSingularTriplets</A>()
<BR><P><B></B><H3><FONT COLOR="#883300">Level</FONT></H3>beginner<BR>
<H3><FONT COLOR="#883300">Location</FONT></H3>
</B><A HREF="../../../src/svd/interface/svdsolve.c.html#SVDGetSingularTriplet">src/svd/interface/svdsolve.c</A>
<P><H3><FONT COLOR="#883300">Examples</FONT></H3>
<A HREF="../../../src/svd/tutorials/ex8.c.html">src/svd/tutorials/ex8.c</A><BR>
<A HREF="../../../src/svd/tutorials/ex15.c.html">src/svd/tutorials/ex15.c</A><BR>
<A HREF="../../../src/svd/tutorials/ex15f.F90.html">src/svd/tutorials/ex15f.F90</A><BR>
<A HREF="../../../src/svd/tutorials/ex45.c.html">src/svd/tutorials/ex45.c</A><BR>
<A HREF="../../../src/svd/tutorials/ex52.c.html">src/svd/tutorials/ex52.c</A><BR>
<A HREF="../../../src/svd/tutorials/ex53.c.html">src/svd/tutorials/ex53.c</A><BR>
<BR><BR><A HREF="./index.html">Index of all SVD routines</A>
<BR><A HREF="../../../docs/manual.html">Table of Contents for all manual pages</A>
<BR><A HREF="../singleindex.html">Index of all manual pages</A>
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