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<H1><A NAME="SECTION000110000000000000000"></A>
<A NAME="sec:precs"></A>
<BR>
Preconditioner routines
</H1>

<P>
<A NAME="sec:psprecs"></A>The base PSBLAS library  contains the implementation of two simple
preconditioning techniques:

<UL>
<LI>Diagonal Scaling
</LI>
<LI>Block Jacobi with ILU(0) factorization
</LI>
</UL>
The supporting data type and subroutine interfaces are defined in the
module  <code>psb_prec_mod</code>.

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<LI><A NAME="tex2html1421"
  HREF="node100.html">psb_precinit -- Initialize a  preconditioner</A>
<LI><A NAME="tex2html1422"
  HREF="node101.html">psb_precbld -- Builds a preconditioner</A>
<LI><A NAME="tex2html1423"
  HREF="node102.html">psb_precaply -- Preconditioner application routine</A>
<LI><A NAME="tex2html1424"
  HREF="node103.html">psb_precdescr -- Prints a description of current
  preconditioner</A>
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