Thank you sir. Just one last question. So if I have the same problem coded in real+imaginary or complex and solve with SparseDirect solver or Krylov subspace methods. Will there be difference in time consumption (due to larger matirx / or harder to solve complex arithmetic embedded in those solver)?
在2022年9月28日星期三 UTC+8 10:57:13<Wolfgang Bangerth> 写道： > On 9/27/22 20:52, 'yy.wayne' via deal.II User Group wrote: > > I'm using the Oracle VirtualBox environment by default, so I guess it's > not > > complied with PETSc complex arithmetic. > > Yes, that's probably true. You will have to install things from scratch on > your system if you want PETSc with complex arithmetic. It is a pity that > PETSc > doesn't make that easy :-( > > > > By the way, is using complex coding approved or separate to real and > imaginary > > parts? I read another discussion in gouglegroup said complex coding > might lead > > to error for <u,v> <v,u> integral. But separate a problem into real and > > imaginary doubles the matirx size and DoFs, isn't it? > > Well yes, but then you do need to store real and imaginary parts somewhere > anyway. So this isn't likely going to be a big bottleneck. > > The post you refer to simply points out that it is easy to make mistakes > if > you work in complex, rather than separate real/imaginary, arithmetic. But > it > can be done correctly, as shown in step-58. > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > www: http://www.math.colostate.edu/~bangerth/ > > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/04ced81f-0cb7-4b9c-970c-84926ae4fb14n%40googlegroups.com.
