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<div id="version" align=right><b>petsc-3.14.5 2021-03-03</b></div>
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<A NAME="SNESLINESEARCHBASIC"><H1>SNESLINESEARCHBASIC</H1></A>
This line search implementation is not a line search at all; it simply uses the full step. Thus, this routine is intended for methods with well-scaled updates; i.e. Newton's method (<A HREF="../SNES/SNESNEWTONLS.html#SNESNEWTONLS">SNESNEWTONLS</A>), on well-behaved problems.
<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>-snes_linesearch_damping <damping> </B></TD><TD>- search vector is scaled by this amount, default is 1.0
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-snes_linesearch_norms <flag> </B></TD><TD>- whether to compute norms or not, default is true (<A HREF="../SNES/SNESLineSearchSetComputeNorms.html#SNESLineSearchSetComputeNorms">SNESLineSearchSetComputeNorms</A>())
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
For methods with ill-scaled updates (<A HREF="../SNES/SNESNRICHARDSON.html#SNESNRICHARDSON">SNESNRICHARDSON</A>, <A HREF="../SNES/SNESNCG.html#SNESNCG">SNESNCG</A>), a small
damping parameter may yield satisfactory but slow convergence despite
the simplicity of the line search.
<P>
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../SNES/SNESLineSearchCreate.html#SNESLineSearchCreate">SNESLineSearchCreate</A>(), <A HREF="../SNES/SNESLineSearchSetType.html#SNESLineSearchSetType">SNESLineSearchSetType</A>(), <A HREF="../SNES/SNESLineSearchSetDamping.html#SNESLineSearchSetDamping">SNESLineSearchSetDamping</A>(), <A HREF="../SNES/SNESLineSearchSetComputeNorms.html#SNESLineSearchSetComputeNorms">SNESLineSearchSetComputeNorms</A>()
<BR><P><B></B><H3><FONT COLOR="#CC3333">Level</FONT></H3>advanced<BR>
<H3><FONT COLOR="#CC3333">Location</FONT></H3>
</B><A HREF="../../../src/snes/linesearch/impls/basic/linesearchbasic.c.html#SNESLINESEARCHBASIC">src/snes/linesearch/impls/basic/linesearchbasic.c</A>
<P><H3><FONT COLOR="#CC3333">Examples</FONT></H3>
<A HREF="../../../src/ts/tutorials/ex22.c.html">src/ts/tutorials/ex22.c.html</A><BR>
<A HREF="../../../src/ts/tutorials/ex22f.F.html">src/ts/tutorials/ex22f.F.html</A><BR>
<A HREF="../../../src/ts/utils/dmplexlandau/tutorials/ex1.c.html">src/ts/utils/dmplexlandau/tutorials/ex1.c.html</A><BR>
<A HREF="../../../src/ts/utils/dmplexlandau/tutorials/ex1f90.F90.html">src/ts/utils/dmplexlandau/tutorials/ex1f90.F90.html</A><BR>
<BR><A HREF="./index.html">Index of all SNES routines</A>
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