<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">

<!--Converted with LaTeX2HTML 2008 (1.71)
original version by:  Nikos Drakos, CBLU, University of Leeds
* revised and updated by:  Marcus Hennecke, Ross Moore, Herb Swan
* with significant contributions from:
  Jens Lippmann, Marek Rouchal, Martin Wilck and others -->
<HTML>
<HEAD>
<TITLE>User Interface</TITLE>
<META NAME="description" CONTENT="User Interface">
<META NAME="keywords" CONTENT="userhtml">
<META NAME="resource-type" CONTENT="document">
<META NAME="distribution" CONTENT="global">

<META NAME="Generator" CONTENT="LaTeX2HTML v2008">
<META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css">

<LINK REL="STYLESHEET" HREF="userhtml.css">

<LINK REL="next" HREF="node23.html">
<LINK REL="previous" HREF="node14.html">
<LINK REL="up" HREF="userhtml.html">
<LINK REL="next" HREF="node17.html">
</HEAD>

<BODY >
<!--Navigation Panel-->
<A NAME="tex2html254"
  HREF="node17.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> 
<A NAME="tex2html250"
  HREF="userhtml.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> 
<A NAME="tex2html244"
  HREF="node15.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> 
<A NAME="tex2html252"
  HREF="node2.html">
<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A>  
<BR>
<B> Next:</B> <A NAME="tex2html255"
  HREF="node17.html">Subroutine mld_precinit</A>
<B> Up:</B> <A NAME="tex2html251"
  HREF="userhtml.html">userhtml</A>
<B> Previous:</B> <A NAME="tex2html245"
  HREF="node15.html">Examples</A>
 &nbsp; <B>  <A NAME="tex2html253"
  HREF="node2.html">Contents</A></B> 
<BR>
<BR>
<!--End of Navigation Panel-->

<H1><A NAME="SECTION00080000000000000000"></A><A NAME="sec:userinterface"></A>
<BR>
User Interface
</H1>

<P>
The basic user interface of MLD2P4 consists of six routines. The four routines <code>mld_</code> <code>precinit</code>,
<code>mld_precset</code>, <code>mld_precbld</code> and <code>mld_precaply</code> encapsulate all the functionalities
for the setup and the application of any one-level and multi-level
preconditioner implemented in the package.
The routine <code>mld_precfree</code> deallocates the preconditioner data structure, while
<code>mld_precdescr</code> prints a description of the preconditioner setup by the user.

<P>
For each routine, the same user interface is overloaded with
respect to the real/complex case and the single/double precision;
arguments with appropriate data types must be passed to the routine,
i.e.

<UL>
<LI>the sparse matrix data structure, containing the matrix to be
  preconditioned, must be of type <code>mld_</code><I>x</I><code>spmat_type</code>
	with <I>x</I> = <code>s</code> for real single precision, <I>x</I> = <code>d</code>
	for real double precision, <I>x</I> = <code>c</code> for complex single precision,
	<I>x</I> = <code>z</code> for complex double precision;
</LI>
<LI>the preconditioner data structure must be of type
  <code>mld_</code><I>x</I><code>prec_type</code>, with <I>x</I> =    
  <code>s</code>, <code>d</code>, <code>c</code>, <code>z</code>, according to the sparse
  matrix data structure;
</LI>
<LI>the arrays containing the vectors <IMG
 WIDTH="14" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
 SRC="img22.png"
 ALT="$v$"> and <IMG
 WIDTH="17" HEIGHT="18" ALIGN="BOTTOM" BORDER="0"
 SRC="img89.png"
 ALT="$w$"> involved in
  the preconditioner application <IMG
 WIDTH="86" HEIGHT="21" ALIGN="BOTTOM" BORDER="0"
 SRC="img61.png"
 ALT="$w=M^{-1}v$"> must be of type   
  <I>type</I><code>(</code><I>kind_parameter</I><code>)</code>, with <I>type</I> =
  <code>real</code>, <code>complex</code> and <I>kind_parameter</I> = <code>kind(1.e0)</code>,
  <code>kind(1.d0)</code>, according to the sparse matrix and preconditioner
  data structure; note that the PSBLAS module <code>psb_base_mod</code>
  provides the constants <code>psb_spk_</code>
  = <code>kind(1.e0)</code> and <code>psb_dpk_</code> = <code>kind(1.d0)</code>;
</LI>
<LI>real parameters defining the preconditioner must be declared
  according to the precision of the sparse matrix and preconditioner
  data structures (see Section&nbsp;<A HREF="node18.html#sec:precset">6.2</A>).
</LI>
</UL>
A description of each routine is given in the remainder of this section.

<P>

<P>
<BR><HR>
<!--Table of Child-Links-->
<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></A>

<UL>
<LI><A NAME="tex2html256"
  HREF="node17.html">Subroutine mld_precinit</A>
<LI><A NAME="tex2html257"
  HREF="node18.html">Subroutine mld_precset</A>
<LI><A NAME="tex2html258"
  HREF="node19.html">Subroutine mld_precbld</A>
<LI><A NAME="tex2html259"
  HREF="node20.html">Subroutine mld_precaply</A>
<LI><A NAME="tex2html260"
  HREF="node21.html">Subroutine mld_precfree</A>
<LI><A NAME="tex2html261"
  HREF="node22.html">Subroutine mld_precdescr</A>
</UL>
<!--End of Table of Child-Links-->
<HR>
<!--Navigation Panel-->
<A NAME="tex2html254"
  HREF="node17.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> 
<A NAME="tex2html250"
  HREF="userhtml.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> 
<A NAME="tex2html244"
  HREF="node15.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A> 
<A NAME="tex2html252"
  HREF="node2.html">
<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A>  
<BR>
<B> Next:</B> <A NAME="tex2html255"
  HREF="node17.html">Subroutine mld_precinit</A>
<B> Up:</B> <A NAME="tex2html251"
  HREF="userhtml.html">userhtml</A>
<B> Previous:</B> <A NAME="tex2html245"
  HREF="node15.html">Examples</A>
 &nbsp; <B>  <A NAME="tex2html253"
  HREF="node2.html">Contents</A></B> 
<!--End of Navigation Panel-->

</BODY>
</HTML>