[Getdp] result all zero

[Christophe Geuzaine]

Lin Ji wrote:
> 
> Hello,
>     I am trying to solve the Helmholtz equation (Fourier transform of the
> wave equation in time) just for one frequency but get all zero result. Can
> you take a look of my .pro and SOLVER.PAR file? I am using getdp-0.821.

Are you trying to solve your problem in the frequency domain? Then you
forgot to specify the frequency in the System definition. 

>     Also, is the parameter setting in SOLVER.PAR very important for solving a
> particular PDE? I am not so familiar with choosing the various algorithms.
> Could you recommend some books on the suject. The book
>        Iterative methods for sparse linear systems
> by Y. Saad you recommend before is outof print.

The parameters should be adapted to the kind of system you want to
solve. If you cannot find Saad's book, try to read 

@book{barret-templates-95,
  author =	 "R. Barrett and M. Berry and T. F. Chan and J. Demmel
                  and J. Donato and J. Dongarra and V. Eijkhout and
                  R. Pozo and C. Romine and H. Van der Vorst",
  title =	 "Templates for the Solution of Linear Systems-
                  Building Blocks for Iterative Methods",
  publisher =	 SIAM,
  year =	 1995
}

I know it's available for free on the web, but I don't remember where.

Christophe

-- 
Christophe Geuzaine

Tel: 32 (0) 4 366 37 10    http://geuz.org
Fax: 32 (0) 4 366 29 10    mailto:Christophe.Geuzaine at ulg.ac.be