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<div id="version" align=right><b>slepc-3.23.1 2025-05-01</b></div>
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<H1>DSGetMat</H1>
Returns a sequential dense <A HREF="https://petsc.org/release/manualpages/Mat/Mat.html#Mat">Mat</A> object containing the requested matrix.
<H3><FONT COLOR="#883300">Synopsis</FONT></H3>
<PRE>
#include "slepcds.h"
<A HREF="https://petsc.org/release/manualpages/Sys/PetscErrorCode.html#PetscErrorCode">PetscErrorCode</A> <A HREF="../DS/DSGetMat.html#DSGetMat">DSGetMat</A>(<A HREF="../DS/DS.html#DS">DS</A> ds,<A HREF="../DS/DSMatType.html#DSMatType">DSMatType</A> m,<A HREF="https://petsc.org/release/manualpages/Mat/Mat.html#Mat">Mat</A> *A)
</PRE>
Not Collective
<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>ds </B></TD><TD> - the direct solver context
</TD></TR>
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>m </B></TD><TD> - the requested matrix
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Output Parameter</FONT></H3>
<TABLE border="0" cellpadding="0" cellspacing="0">
<TR><TD WIDTH=40></TD><TD ALIGN=LEFT VALIGN=TOP><B>A </B></TD><TD> - <A HREF="https://petsc.org/release/manualpages/Mat/Mat.html#Mat">Mat</A> object
</TD></TR></TABLE>
<P>
<H3><FONT COLOR="#883300">Notes</FONT></H3>
The returned <A HREF="https://petsc.org/release/manualpages/Mat/Mat.html#Mat">Mat</A> has sizes equal to the current <A HREF="../DS/DS.html#DS">DS</A> dimensions (nxm),
and contains the values that would be obtained with <A HREF="../DS/DSGetArray.html#DSGetArray">DSGetArray</A>()
(not <A HREF="../DS/DSGetArrayReal.html#DSGetArrayReal">DSGetArrayReal</A>()). If the <A HREF="../DS/DS.html#DS">DS</A> was truncated, then the number of rows
is equal to the dimension prior to truncation, see <A HREF="../DS/DSTruncate.html#DSTruncate">DSTruncate</A>().
The communicator is always <A HREF="https://petsc.org/release/manualpages/Sys/PETSC_COMM_SELF.html#PETSC_COMM_SELF">PETSC_COMM_SELF</A>.
<P>
It is implemented with <A HREF="https://petsc.org/release/manualpages/Mat/MatDenseGetSubMatrix.html#MatDenseGetSubMatrix">MatDenseGetSubMatrix</A>(), and when no longer needed
the user must call <A HREF="../DS/DSRestoreMat.html#DSRestoreMat">DSRestoreMat</A>() which will invoke <A HREF="https://petsc.org/release/manualpages/Mat/MatDenseRestoreSubMatrix.html#MatDenseRestoreSubMatrix">MatDenseRestoreSubMatrix</A>().
<P>
For matrices <A HREF="../DS/DSMatType.html#DSMatType">DS_MAT_T</A> and <A HREF="../DS/DSMatType.html#DSMatType">DS_MAT_D</A>, this function will return a <A HREF="https://petsc.org/release/manualpages/Mat/Mat.html#Mat">Mat</A> object
that cannot be used directly for computations, since it uses compact storage
(three and one diagonals for T and D, respectively). In complex scalars, the
internal array stores real values, so it is sufficient with 2 columns for T.
<P>
<P>
<H3><FONT COLOR="#883300">See Also</FONT></H3>
<A HREF="../DS/DSRestoreMat.html#DSRestoreMat">DSRestoreMat</A>(), <A HREF="../DS/DSSetDimensions.html#DSSetDimensions">DSSetDimensions</A>(), <A HREF="../DS/DSGetArray.html#DSGetArray">DSGetArray</A>(), <A HREF="../DS/DSGetArrayReal.html#DSGetArrayReal">DSGetArrayReal</A>(), <A HREF="../DS/DSTruncate.html#DSTruncate">DSTruncate</A>()
<BR><P><B></B><H3><FONT COLOR="#883300">Level</FONT></H3>advanced<BR>
<H3><FONT COLOR="#883300">Location</FONT></H3>
</B><A HREF="../../../src/sys/classes/ds/interface/dsops.c.html#DSGetMat">src/sys/classes/ds/interface/dsops.c</A>
<BR><BR><A HREF="./index.html">Index of all DS routines</A>
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