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
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
<HTML>
<HEAD> <link rel="canonical" href="http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatMFFDSetType.html" />
<META NAME="GENERATOR" CONTENT="DOCTEXT">
<TITLE>MatMFFDSetType</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/Mat/MatMFFDSetType.html "><small>Report Typos and Errors</small></a></div>
<A NAME="MatMFFDSetType"><H1>MatMFFDSetType</H1></A>
Sets the method that is used to compute the differencing parameter for finite differene matrix-free formulations.
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscmat.h"
PetscErrorCode MatMFFDSetType(Mat mat,MatMFFDType ftype)
</PRE>
<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>mat </B></TD><TD>- the "matrix-free" matrix created via <A HREF="../SNES/MatCreateSNESMF.html#MatCreateSNESMF">MatCreateSNESMF</A>(), or <A HREF="../Mat/MatCreateMFFD.html#MatCreateMFFD">MatCreateMFFD</A>()
or <A HREF="../Mat/MatSetType.html#MatSetType">MatSetType</A>(mat,<A HREF="../Mat/MATMFFD.html#MATMFFD">MATMFFD</A>);
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>ftype </B></TD><TD>- the type requested, either <A HREF="../Mat/MATMFFD_WP.html#MATMFFD_WP">MATMFFD_WP</A> or <A HREF="../Mat/MATMFFD_DS.html#MATMFFD_DS">MATMFFD_DS</A>
</TD></TR></TABLE>
<P>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
For example, such routines can compute h for use in
Jacobian-vector products of the form
<P>
F(x+ha) - F(x)
F'(u)a ~= ----------------
h
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../SNES/MatCreateSNESMF.html#MatCreateSNESMF">MatCreateSNESMF</A>(), <A HREF="../Mat/MatMFFDRegister.html#MatMFFDRegister">MatMFFDRegister</A>(), <A HREF="../Mat/MatMFFDSetFunction.html#MatMFFDSetFunction">MatMFFDSetFunction</A>(), <A HREF="../Mat/MatCreateMFFD.html#MatCreateMFFD">MatCreateMFFD</A>()
<BR><P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>advanced
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/mat/impls/mffd/mffd.c.html#MatMFFDSetType">src/mat/impls/mffd/mffd.c</A>
<BR><A HREF="./index.html">Index of all Mat 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>
|