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<DIV dir=ltr align=left><SPAN class=140484003-18012011><FONT size=2>See the
emails in this thread "KSPLSQR convergence criterion" for</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=140484003-18012011><FONT size=2>explicit
calls for LSQR and some more info.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=140484003-18012011><FONT size=2><A
href="http://lists.mcs.anl.gov/pipermail/petsc-users/2010-August/thread.html#6784">http://lists.mcs.anl.gov/pipermail/petsc-users/2010-August/thread.html#6784</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=140484003-18012011><FONT
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=140484003-18012011><FONT
size=2>Chetan</FONT></SPAN></DIV><BR>
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<FONT size=2><B>From:</B> petsc-users-bounces@mcs.anl.gov
[mailto:petsc-users-bounces@mcs.anl.gov] <B>On Behalf Of </B>Gaurish
Telang<BR><B>Sent:</B> Monday, January 17, 2011 01:16 AM<BR><B>To:</B>
petsc-users@mcs.anl.gov<BR><B>Subject:</B> [petsc-users] using KSPLSQR and
SKPCGNE<BR></FONT><BR></DIV>
<DIV></DIV>Hi,<BR><BR>I am new to PETSc and I wanted to solve some least
squares problems with it. On searching the net I found that KSPLSQR() and
KSPCGNE() solve the least squares system |Ax-b|<BR><BR>But I don't really know
how to use these functions to get my answer. This manual page did not help: <A
href="http://www.mcs.anl.gov/petsc/petsc-2/snapshots/petsc-current/docs/manualpages/KSP/KSPLSQR.html">http://www.mcs.anl.gov/petsc/petsc-2/snapshots/petsc-current/docs/manualpages/KSP/KSPLSQR.html</A><BR><BR>Apparently
no tutorial code uses these functions. <BR><BR>If anyone could could give a
small code snippet of how to use these functions (assuming A and b are given)
then it would be really helpful.
<BR><BR>Thanks,<BR><BR>Gaurish<BR></BLOCKQUOTE></BODY></HTML>