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["Anglade Pierre-Matthieu" <anglade@gmail.com>]

Usually, most complex data in abinit are trreated as array of double
precision real. However, in the gw part some routines uses the complex
and complex(dp) kinds. It is an awfull bug to have sometimes things
declared as single precision and sometimes as double precision numbers
and it has been corrected already in some branches of the 
abinit-devel--*--5.2. 
From the correction I've made, for as much as I remember, I'm almost
sure that there is no single precision bug within the internal
routines. It was just some things in the output part...

regards

PMA

On 5/20/06, dylu@ucdavis.edu <dylu@ucdavis.edu> wrote:

Hello, I've a question regarding the precision of complex variables, such as
omega and epsilon in a GW calculation. I'm kind of confused by the way they are handled. To be specific, in the routine to evaluate plasmon pole parameters "cppm1par.F90", they are declared as single precision:

complex,intent(in) :: epsm1(npwvec,npwvec,nomega,nq),omega(nomega)

Before being written into a SCR file, however, they are converted to double precision in wrscr.F90

     complex,intent(in) :: epsm1(npwsigx,npwsigx,nomega),omega(nomega)
     complex (kind(0.0d0)),allocatable :: epsm1d(:,:),omegad(:)
......
       omegad(:) = omega(:)
       epsm1d(:,:) = epsm1(:,:,io)

I'm wondering if complex data are treated as single precision in the main codes of  abinit. If it is the case, it would deteriorate the GW results.

Thanks
Deyu

-- 
Pierre-Matthieu Anglade