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<div id="version" align=right><b>petsc-3.4.2 2013-07-02</b></div>
<A NAME="KSPRichardsonSetSelfScale"><H1>KSPRichardsonSetSelfScale</H1></A>
Sets Richardson to automatically determine optimal scaling at each iteration to minimize the 2-norm of the preconditioned residual
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscksp.h"
PetscErrorCode KSPRichardsonSetSelfScale(KSP ksp,PetscBool scale)
</PRE>
Logically Collective on <A HREF="../KSP/KSP.html#KSP">KSP</A>
<P>
<H3><FONT COLOR="#CC3333">Input Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>ksp </B></TD><TD>- the iterative context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>scale </B></TD><TD>- <A HREF="../Sys/PETSC_TRUE.html#PETSC_TRUE">PETSC_TRUE</A> or the default of <A HREF="../Sys/PETSC_FALSE.html#PETSC_FALSE">PETSC_FALSE</A>
</TD></TR></TABLE>
<P>
<P>
Notes: Requires two extra work vectors. Uses an extra <A HREF="../Vec/VecAXPY.html#VecAXPY">VecAXPY</A>() and <A HREF="../Vec/VecDotNorm2.html#VecDotNorm2">VecDotNorm2</A>() per iteration.
<P>
Developer Notes: Could also minimize the 2-norm of the true residual with one less work vector
<P>
<P>
<H3><FONT COLOR="#CC3333">Keywords</FONT></H3>
<A HREF="../KSP/KSP.html#KSP">KSP</A>, Richardson, set, scale
<BR><P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>intermediate
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/ksp/ksp/impls/rich/richscale.c.html#KSPRichardsonSetSelfScale">src/ksp/ksp/impls/rich/richscale.c</A>
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