[Fortran] Is anyone familiar with the Elk-code software?

[Douasing]

Dear all,

Are you familiar with the Elk-code software? It is a software about FLAPW (full potential linear augumented plane wave).Recently,I am reading the source code,but I meet many difficulties.

For example,I've a question related to charge density.In the Elk source code, the charge density is divided two parts,i.e.,rhomt(:,:,:) in the spherical coordinates and rhoir(:) in the Cartesian coordinates.But I don't find the angle (theta,phi) for the rhomt(:,:,:) and the position(x,y,z) for the rhoir(:) in the "rhomag.f90".
In addition,I want to learn about the calculating of the exchange-correlation energy density and potential,but I still can't find the (theta,phi) and (x,y,z),taking the xc_xalpha.f90 as an exmaple as follows:

! loop over density points
do i=1,n
r=rho(i)
if (r.gt.1.d-12) then
rs=(3.d0/(4.d0pir))(1.d0/3.d0)
rsm1=1.0d0/rs
! compute energy density
exc(i)=-alphaefacrsm1
! compute potential
vxc(i)=-alphavfacrsm1
end if
end do

Here,the "i=1,n" stands for the value of the radial meshgrid in the muffin-tin sphere and the value of G-point in the interstitial region.As my understanding,the energy density or potential should be for every point in the real space,so I don't clear why the (theta,phi) and (x,y,z) can't be found in those subroutines.

If anyone give me a hint or a suggestion,I will be thankful.
Regards,

 

[Douasing]

By the way,if anyone will think my question is not clear enough, please say it to me,I will do my best to describe it.