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<H1>SVDSetInitialSpaceLeft</H1>
Specify a basis of vectors that constitute the initial left space, that is, a rough approximation to the left singular subspace from which the solver starts to iterate.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcsvd.h"
PetscErrorCode SVDSetInitialSpaceLeft(SVD svd,PetscInt n,Vec *is)
</PRE>
Collective on <A HREF="../SVD/SVD.html#SVD">SVD</A> and Vec
<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>n </B></TD><TD> - number of vectors
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>is </B></TD><TD> - set of basis vectors of the initial space
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
Some solvers start to iterate on a single vector (initial vector). In that case,
the other vectors are ignored.
<P>
These vectors do not persist from one <A HREF="../SVD/SVDSolve.html#SVDSolve">SVDSolve</A>() call to the other, so the
initial space should be set every time.
<P>
The vectors do not need to be mutually orthonormal, since they are explicitly
orthonormalized internally.
<P>
Common usage of this function is when the user can provide a rough approximation
of the wanted singular space. Then, convergence may be faster.
<P>
<P><B><FONT COLOR="#883300">Location: </FONT></B><A HREF="../../../src/svd/interface/svdsetup.c.html#SVDSetInitialSpaceLeft">src/svd/interface/svdsetup.c</A>
<BR><A HREF="./index.html">Index of all SVD routines</A>
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