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<div id="version" align=right><b>petsc-3.10.3 2018-12-18</b></div>
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<A NAME="MatCreateLRC"><H1>MatCreateLRC</H1></A>
Creates a new matrix object that behaves like A + U*C*V'
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petscmat.h"
<A HREF="../Sys/PetscErrorCode.html#PetscErrorCode">PetscErrorCode</A> <A HREF="../Mat/MatCreateLRC.html#MatCreateLRC">MatCreateLRC</A>(<A HREF="../Mat/Mat.html#Mat">Mat</A> A,<A HREF="../Mat/Mat.html#Mat">Mat</A> U,<A HREF="../Vec/Vec.html#Vec">Vec</A> c,<A HREF="../Mat/Mat.html#Mat">Mat</A> V,<A HREF="../Mat/Mat.html#Mat">Mat</A> *N)
</PRE>
Collective on <A HREF="../Mat/Mat.html#Mat">Mat</A>
<P>
<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>A </B></TD><TD>- the (sparse) matrix (can be NULL)
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>U, V </B></TD><TD>- two dense rectangular (tall and skinny) matrices
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>c </B></TD><TD>- a sequential vector containing the diagonal of C (can be NULL)
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#CC3333">Output Parameter</FONT></H3>
<DT><B>N </B> -the matrix that represents A + U*C*V'
<br>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
The matrix A + U*C*V' is not formed! Rather the new matrix
object performs the matrix-vector product by first multiplying by
A and then adding the other term.
<P>
C is a diagonal matrix (represented as a vector) of order k,
where k is the number of columns of both U and V.
<P>
If A is NULL then the new object behaves like a low-rank matrix U*C*V'.
<P>
Use V=U (or V=NULL) for a symmetric low-rank correction, A + U*C*U'.
<P>
If c is NULL then the low-rank correction is just U*V'.
<P>
<P>
<H3><FONT COLOR="#CC3333">See Also</FONT></H3>
<A HREF="../Mat/MatLRCGetMats.html#MatLRCGetMats">MatLRCGetMats</A>()
<BR><P><B></B><H3><FONT COLOR="#CC3333">Level</FONT></H3>intermediate<BR>
<H3><FONT COLOR="#CC3333">Location</FONT></H3>
</B><A HREF="../../../src/mat/impls/lrc/lrc.c.html#MatCreateLRC">src/mat/impls/lrc/lrc.c</A>
<P><H3><FONT COLOR="#CC3333">Examples</FONT></H3>
<A HREF="../../../src/tao/pde_constrained/examples/tutorials/elliptic.c.html">src/tao/pde_constrained/examples/tutorials/elliptic.c.html</A><BR>
<BR><A HREF="./index.html">Index of all Mat routines</A>
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