1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
<HTML>
<HEAD>
<META NAME="GENERATOR" CONTENT="DOCTEXT">
<TITLE>PCICC</TITLE>
</HEAD>
<BODY BGCOLOR="FFFFFF">
<A NAME="PCICC"><H1>PCICC</H1></A>
Incomplete Cholesky factorization preconditioners.
<H3><FONT COLOR="#CC3333">Options Database Keys</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_levels <k> </B></TD><TD>- number of levels of fill for ICC(k)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_in_place </B></TD><TD>- only for ICC(0) with natural ordering, reuses the space of the matrix for
its factorization (overwrites original matrix)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_damping </B></TD><TD>- add damping to diagonal to prevent zero (or very small) pivots
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_shift </B></TD><TD>- apply Manteuffel shift to diagonal to force positive definite preconditioner
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_zeropivot <tol> </B></TD><TD>- set tolerance for what is considered a zero pivot
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_fill <nfill> </B></TD><TD>- expected amount of fill in factored matrix compared to original matrix, nfill > 1
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pc_icc_mat_ordering_type <natural,nd,1wd,rcm,qmd> </B></TD><TD>- set the row/column ordering of the factored matrix
</TD></TR></TABLE>
<P>
<P>
<P>
Notes: Only implemented for some matrix formats. Not implemented in parallel
<P>
For BAIJ matrices this implements a point block ICC.
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../PC/PCCreate.html#PCCreate">PCCreate</A>(), <A HREF="../PC/PCSetType.html#PCSetType">PCSetType</A>(), <A HREF="../PC/PCType.html#PCType">PCType</A> (for list of available types), <A HREF="../PC/PC.html#PC">PC</A>, <A HREF="../PC/PCSOR.html#PCSOR">PCSOR</A>, <A HREF="../Mat/MatOrderingType.html#MatOrderingType">MatOrderingType</A>,
<BR>PCICCSetSetZeroPivot(), <A HREF="../PC/PCICCSetDamping.html#PCICCSetDamping">PCICCSetDamping</A>(), <A HREF="../PC/PCICCSetShift.html#PCICCSetShift">PCICCSetShift</A>(),
<A HREF="../PC/PCICCSetFill.html#PCICCSetFill">PCICCSetFill</A>(), <A HREF="../PC/PCICCSetMatOrdering.html#PCICCSetMatOrdering">PCICCSetMatOrdering</A>(), PCICCSetReuseOrdering(),
<A HREF="../PC/PCICCSetLevels.html#PCICCSetLevels">PCICCSetLevels</A>()
<P>
<P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>beginner
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/ksp/pc/impls/icc/icc.c.html#PCICC">src/ksp/pc/impls/icc/icc.c</A>
<BR><A HREF="./index.html">Index of all PC routines</A>
<BR><A HREF="../../index.html">Table of Contents for all manual pages</A>
<BR><A HREF="../singleindex.html">Index of all manual pages</A>
<P><H3><FONT COLOR="#CC3333">Examples</FONT></H3>
<A HREF="../../../src/ksp/pc/examples/tutorials/ex2.c.html">src/ksp/pc/examples/tutorials/ex2.c.html</A><BR>
</BODY></HTML>
|
