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<div id="version" align=right><b>slepc-3.7.3 2016-09-29</b></div>
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<H1>NEPSetDimensions</H1>
Sets the number of eigenvalues to compute and the dimension of the subspace.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcnep.h"
PetscErrorCode NEPSetDimensions(NEP nep,PetscInt nev,PetscInt ncv,PetscInt mpd)
</PRE>
Logically Collective on <A HREF="../NEP/NEP.html#NEP">NEP</A>
<P>
<H3><FONT COLOR="#883300">Input Parameters</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>nep </B></TD><TD> - the nonlinear eigensolver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>nev </B></TD><TD> - number of eigenvalues to compute
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>ncv </B></TD><TD> - the maximum dimension of the subspace to be used by the solver
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>mpd </B></TD><TD> - the maximum dimension allowed for the projected problem
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Options Database Keys</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-nep_nev <nev> </B></TD><TD> - Sets the number of eigenvalues
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-nep_ncv <ncv> </B></TD><TD> - Sets the dimension of the subspace
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-nep_mpd <mpd> </B></TD><TD> - Sets the maximum projected dimension
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
Use PETSC_DEFAULT for ncv and mpd to assign a reasonably good value, which is
dependent on the solution method.
<P>
The parameters ncv and mpd are intimately related, so that the user is advised
to set one of them at most. Normal usage is that
(a) in cases where nev is small, the user sets ncv (a reasonable default is 2*nev); and
(b) in cases where nev is large, the user sets mpd.
<P>
The value of ncv should always be between nev and (nev+mpd), typically
ncv=nev+mpd. If nev is not too large, mpd=nev is a reasonable choice, otherwise
a smaller value should be used.
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../NEP/NEPGetDimensions.html#NEPGetDimensions">NEPGetDimensions</A>()
<BR><P><B><FONT COLOR="#883300">Location: </FONT></B><A HREF="../../../src/nep/interface/nepopts.c.html#NEPSetDimensions">src/nep/interface/nepopts.c</A>
<BR><A HREF="./index.html">Index of all NEP 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="#883300">Examples</FONT></H3>
<A HREF="../../../src/nep/examples/tutorials/ex20.c.html">src/nep/examples/tutorials/ex20.c.html</A><BR>
<A HREF="../../../src/nep/examples/tutorials/ex22.c.html">src/nep/examples/tutorials/ex22.c.html</A><BR>
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