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
49
50
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
<HTML>
<HEAD> <link rel="canonical" href="http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCFactorSetFill.html" />
<META NAME="GENERATOR" CONTENT="DOCTEXT">
<TITLE>PCFactorSetFill</TITLE>
</HEAD>
<BODY BGCOLOR="FFFFFF">
<div id="version" align=right><b>petsc-3.7.5 2017-01-01</b></div>
<div id="bugreport" align=right><a href="mailto:petsc-maint@mcs.anl.gov?subject=Typo or Error in Documentation &body=Please describe the typo or error in the documentation: petsc-3.7.5 v3.7.5 docs/manualpages/PC/PCFactorSetFill.html "><small>Report Typos and Errors</small></a></div>
<A NAME="PCFactorSetFill"><H1>PCFactorSetFill</H1></A>
Indicate the amount of fill you expect in the factored matrix, fill = number nonzeros in factor/number nonzeros in original matrix.
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscpc.h"
PetscErrorCode PCFactorSetFill(PC pc,PetscReal fill)
</PRE>
Not Collective, each process can expect a different amount of fill
<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>pc </B></TD><TD>- the preconditioner context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>fill </B></TD><TD>- amount of expected fill
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#CC3333">Options Database Key</FONT></H3>
<DT><B>-pc_factor_fill <fill> </B> -Sets fill amount
<br>
<P>
<P>
<H3><FONT COLOR="#CC3333">Note</FONT></H3>
For sparse matrix factorizations it is difficult to predict how much
fill to expect. By running with the option -info PETSc will print the
actual amount of fill used; allowing you to set the value accurately for
future runs. Default PETSc uses a value of 5.0
<P>
This parameter has NOTHING to do with the levels-of-fill of ILU(). That is set with <A HREF="../PC/PCFactorSetLevels.html#PCFactorSetLevels">PCFactorSetLevels</A>() or -pc_factor_levels.
<P>
<P>
<H3><FONT COLOR="#CC3333">Keywords</FONT></H3>
<A HREF="../PC/PC.html#PC">PC</A>, set, factorization, direct, fill
<BR>
<P>
<P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>intermediate
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/ksp/pc/impls/factor/factor.c.html#PCFactorSetFill">src/ksp/pc/impls/factor/factor.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>
</BODY></HTML>
|
