You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
142 lines
3.9 KiB
HTML
142 lines
3.9 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
|
|
|
|
<!--Converted with LaTeX2HTML 2012 (1.2)
|
|
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>psb_precinit -- Initialize a preconditioner</TITLE>
|
|
<META NAME="description" CONTENT="psb_precinit -- Initialize a preconditioner">
|
|
<META NAME="keywords" CONTENT="userhtml">
|
|
<META NAME="resource-type" CONTENT="document">
|
|
<META NAME="distribution" CONTENT="global">
|
|
|
|
<META NAME="Generator" CONTENT="LaTeX2HTML v2012">
|
|
<META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css">
|
|
|
|
<LINK REL="STYLESHEET" HREF="userhtml.css">
|
|
|
|
<LINK REL="next" HREF="node123.html">
|
|
<LINK REL="previous" HREF="node121.html">
|
|
<LINK REL="up" HREF="node121.html">
|
|
<LINK REL="next" HREF="node123.html">
|
|
</HEAD>
|
|
|
|
<BODY >
|
|
<!--Navigation Panel-->
|
|
<A NAME="tex2html1774"
|
|
HREF="node123.html">
|
|
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A>
|
|
<A NAME="tex2html1770"
|
|
HREF="node121.html">
|
|
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A>
|
|
<A NAME="tex2html1764"
|
|
HREF="node121.html">
|
|
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A>
|
|
<A NAME="tex2html1772"
|
|
HREF="node1.html">
|
|
<IMG WIDTH="65" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="contents" SRC="contents.png"></A>
|
|
<BR>
|
|
<B> Next:</B> <A NAME="tex2html1775"
|
|
HREF="node123.html">psb_precbld Builds</A>
|
|
<B> Up:</B> <A NAME="tex2html1771"
|
|
HREF="node121.html">Preconditioner routines</A>
|
|
<B> Previous:</B> <A NAME="tex2html1765"
|
|
HREF="node121.html">Preconditioner routines</A>
|
|
<B> <A NAME="tex2html1773"
|
|
HREF="node1.html">Contents</A></B>
|
|
<BR>
|
|
<BR>
|
|
<!--End of Navigation Panel-->
|
|
|
|
<H2><A NAME="SECTION000111000000000000000">
|
|
psb_precinit -- Initialize a preconditioner</A>
|
|
</H2>
|
|
|
|
<P>
|
|
<PRE>
|
|
call psb_precinit(prec, ptype, info)
|
|
</PRE>
|
|
|
|
<P>
|
|
<DL>
|
|
<DT><STRONG>Type:</STRONG></DT>
|
|
<DD>Asynchronous.
|
|
</DD>
|
|
<DT><STRONG><B>On Entry</B></STRONG></DT>
|
|
<DD>
|
|
</DD>
|
|
<DT><STRONG>ptype</STRONG></DT>
|
|
<DD>the type of preconditioner.
|
|
Scope: <B>global</B>
|
|
<BR>
|
|
Type: <B>required</B>
|
|
<BR>
|
|
Intent: <B>in</B>.
|
|
<BR>
|
|
Specified as: a character string, see usage notes.
|
|
</DD>
|
|
<DT><STRONG><B>On Exit</B></STRONG></DT>
|
|
<DD><P>
|
|
</DD>
|
|
<DT><STRONG>prec</STRONG></DT>
|
|
<DD>Scope: <B>local</B>
|
|
<BR>
|
|
Type: <B>required</B>
|
|
<BR>
|
|
Intent: <B>inout</B>.
|
|
<BR>
|
|
Specified as: a preconditioner data structure precdata<TT>psb_prec_type</TT>.
|
|
</DD>
|
|
<DT><STRONG>info</STRONG></DT>
|
|
<DD>Scope: <B>global</B>
|
|
<BR>
|
|
Type: <B>required</B>
|
|
<BR>
|
|
Intent: <B>out</B>.
|
|
<BR>
|
|
Error code: if no error, 0 is returned.
|
|
</DD>
|
|
</DL>
|
|
<FONT SIZE="+1"><B>Notes</B></FONT>Legal inputs to this subroutine are interpreted depending on the
|
|
<IMG
|
|
WIDTH="41" HEIGHT="30" ALIGN="MIDDLE" BORDER="0"
|
|
SRC="img154.png"
|
|
ALT="$ptype$"> string as follows<A NAME="tex2html30"
|
|
HREF="footnode.html#foot7514"><SUP>3</SUP></A>:
|
|
<DL>
|
|
<DT><STRONG>NONE</STRONG></DT>
|
|
<DD>No preconditioning, i.e. the preconditioner is just a copy
|
|
operator.
|
|
</DD>
|
|
<DT><STRONG>DIAG</STRONG></DT>
|
|
<DD>Diagonal scaling; each entry of the input vector is
|
|
multiplied by the reciprocal of the sum of the absolute values of
|
|
the coefficients in the corresponding row of matrix <IMG
|
|
WIDTH="16" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
|
|
SRC="img1.png"
|
|
ALT="$A$">;
|
|
</DD>
|
|
<DT><STRONG>BJAC</STRONG></DT>
|
|
<DD>Precondition by a factorization of the
|
|
block-diagonal of matrix <IMG
|
|
WIDTH="16" HEIGHT="14" ALIGN="BOTTOM" BORDER="0"
|
|
SRC="img1.png"
|
|
ALT="$A$">, where block boundaries are determined
|
|
by the data allocation boundaries for each process; requires no
|
|
communication. Only the incomplete factorization <IMG
|
|
WIDTH="56" HEIGHT="32" ALIGN="MIDDLE" BORDER="0"
|
|
SRC="img155.png"
|
|
ALT="$ILU(0)$"> is
|
|
currently implemented.
|
|
</DD>
|
|
</DL>
|
|
|
|
<P>
|
|
<BR><HR>
|
|
|
|
</BODY>
|
|
</HTML>
|