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<H1>IPNorm</H1>
Computes the norm of a vector as the square root of the inner product (x,x) as defined by <A HREF="../IP/IPInnerProduct.html#IPInnerProduct">IPInnerProduct</A>().
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcip.h"
PetscErrorCode IPNorm(IP ip,Vec x,PetscReal *norm)
</PRE>
Collective on <A HREF="../IP/IP.html#IP">IP</A> and Vec
<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>ip </B></TD><TD> - the inner product context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>x </B></TD><TD> - input vector
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Output Parameter</FONT></H3>
<DT><B>norm </B> - the computed norm
<br>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
This function will usually compute the 2-norm of a vector, ||x||_2. But
this behaviour may be different if using a non-standard inner product changed
via <A HREF="../IP/IPSetMatrix.html#IPSetMatrix">IPSetMatrix</A>(). For example, if using the B-inner product for
positive definite B, (x,y)_B=y^H Bx, then the computed norm is ||x||_B =
sqrt(x^H Bx).
<P>
In an indefinite inner product, matrix B is indefinite and the norm is
defined as s*sqrt(abs(x^H Bx)), where s = sign(x^H Bx).
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../IP/IPInnerProduct.html#IPInnerProduct">IPInnerProduct</A>()
<BR><P><B><FONT COLOR="#883300">Location: </FONT></B><A HREF="../../../src/ip/ipdot.c.html#IPNorm">src/ip/ipdot.c</A>
<BR><A HREF="./index.html">Index of all IP routines</A>
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