<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi Mark,<div><br></div><div>AMG for complex systems is an active research area. Neither Hypre or ML support directly solving the complex systems. Both at this point would</div><div>require recasting the system as a real system but, at least for Hypre, building PETSc with HYPRE with complex turned on causes problems as you</div><div>cannot build Hypre with complex types. We have been exploring hooking a real build of HYPRE into a complex build of PETSC but our progress lately</div><div>has stalled due to other commitments. In any case, I'd suggest the reference comparing real equivalent versus complex.</div><div><br></div><div><span class="Apple-style-span" style="font-size: 12px; ">MacLachlan and Oosterlee. Algebraic multigrid solvers for complex-valued matrices. SIAM Journal on Scientific Computing (2008) vol. 30 (3) pp. 1548-1571</span></div><div><br></div><div>Travis</div><div><br></div><div><div>
<span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^</div><div>Travis Austin, Ph.D.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Tech-X Corporation</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">5621 Arapahoe Ave, Suite A</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Boulder, CO 80303</div><div><a href="mailto:austin@txcorp.com">austin@txcorp.com</a></div><div>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^</div><br class="Apple-interchange-newline"></span></span>
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<br><div><div>On Mar 23, 2011, at 5:48 AM, Nun ion wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hello all, <br><br>I am interested in using AMG for PETSc, where my matrices are complex. I looked at the documentation for Hypre and I'm not sure that it supports complex arithmetic. I also looked at ML from trilinos, however the only work around would be to recast my problem as a real system (doubling the MATVEcs). Any suggestions?<br>
<br>Thanks<br><br>Mark<br>
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