| 12
 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
 51
 52
 53
 54
 55
 
 | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML3.2 EN">
<HTML>
<HEAD> <link rel="canonical" href="https://slepc.upv.es/documentation/current/docs/manualpages/PEP/PEPSetInterval.html" />
<META NAME="GENERATOR" CONTENT="DOCTEXT">
<link rel="stylesheet" href="/slepc.css" type="text/css">
<TITLE>PEPSetInterval</TITLE>
</HEAD>
<BODY BGCOLOR="FFFFFF">
   <div id="version" align=right><b>slepc-3.14.2 2021-02-01</b></div>
   <div id="bugreport" align=right><a href="mailto:slepc-maint@upv.es?subject=Typo or Error in Documentation &body=Please describe the typo or error in the documentation: slepc-3.14.2 v3.14.2 docs/manualpages/PEP/PEPSetInterval.html "><small>Report Typos and Errors</small></a></div>
<H1>PEPSetInterval</H1>
Defines the computational interval for spectrum slicing. 
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcpep.h" 
PetscErrorCode <A HREF="../PEP/PEPSetInterval.html#PEPSetInterval">PEPSetInterval</A>(<A HREF="../PEP/PEP.html#PEP">PEP</A> pep,PetscReal inta,PetscReal intb)
</PRE>
Logically Collective on pep
<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>pep  </B></TD><TD> - eigensolver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>inta </B></TD><TD> - left end of the interval
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>intb </B></TD><TD> - right end of the interval
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Options Database Key</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>-pep_interval <a,b> </B></TD><TD> - set [a,b] as the interval of interest
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
Spectrum slicing is a technique employed for computing all eigenvalues of
symmetric eigenproblems in a given interval. This function provides the
interval to be considered. It must be used in combination with <A HREF="../PEP/PEPWhich.html#PEPWhich">PEP_ALL</A>, see
<A HREF="../PEP/PEPSetWhichEigenpairs.html#PEPSetWhichEigenpairs">PEPSetWhichEigenpairs</A>().
<P>
In the command-line option, two values must be provided. For an open interval,
one can give an infinite, e.g., -pep_interval 1.0,inf or -pep_interval -inf,1.0.
An open interval in the programmatic interface can be specified with
PETSC_MAX_REAL and -PETSC_MAX_REAL.
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
 <A HREF="../PEP/PEPGetInterval.html#PEPGetInterval">PEPGetInterval</A>(), <A HREF="../PEP/PEPSetWhichEigenpairs.html#PEPSetWhichEigenpairs">PEPSetWhichEigenpairs</A>()
<BR><P><B><FONT COLOR="#883300">Location: </FONT></B><A HREF="../../../src/pep/interface/pepbasic.c.html#PEPSetInterval">src/pep/interface/pepbasic.c</A>
<P><H3><FONT COLOR="#883300">Examples</FONT></H3>
<A HREF="../../../src/pep/tutorials/ex38.c.html">src/pep/tutorials/ex38.c.html</A><BR>
<BR><A HREF="./index.html">Index of all PEP 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>
 |