<div class="gmail_quote">On Sat, Dec 24, 2011 at 07:42, TAY wee-beng <span dir="ltr"><<a href="mailto:zonexo@gmail.com">zonexo@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div id=":y1">I am solving 4 linear equations in my cfd code. I have declared them as:<br>
<br>
KSP ksp,ksp_semi_x,ksp_semi_y,ksp_<u></u>semi_z<br>
<br>
PC pc,pc_semi_x,pc_semi_y,pc_<u></u>semi_z<br>
<br>
PCType ptype<br>
<br>
KSPType ksptype<br>
<br>
However, I only want to solve the 1st eqn via hypre (thru command prompt), and the others via KSPBCGS.<br>
<br>
I now add:<br>
<br>
ksp_type richardson -pc_type hypre -pc_type_hypre boomeramg<br>
<br>
Are all the eqns now solved using hypre?<br>
<br>
How should I specify in the command prompt?</div></blockquote></div><br><div>As Matt says, you can use PCFIELDSPLIT to solve the coupled system. If you really want to set up your own KSP for each system, then use</div><div>
<br></div><div><a href="http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/KSP/KSPSetOptionsPrefix.html">http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/KSP/KSPSetOptionsPrefix.html</a></div>