[Pw_forum] Projected phonon DOS

[Yansun Yao]

Dear Pwscf users,
   I am going to calculate the partial phonon DOS (phonon DOS contribution of a
choosen atom). I guess that I should use tetrahedra method and modify
matdyn.f90. But after reading matdyn.f90 and dost.f90, I am not very clear how
to do it. 
   My guess is the following: 
   At first,one needs to extract the contribution of a choosen atom for every
phonon frequency w(q). Then use this "partial" phonon frequency to calculate
"partial" phonon DOS in the subroutine dos_t. Is it right?  If it is, I have no
clue know how to extract the "partial" frequency. Specifically, I don't know how
frequencies square w2() is calculated in matdyn.f90. I am new to this area so
maybe my guess is totally wrong. Could you give me some hints?
   Could anybody help me? Thanks in advance!

                                 Yansun Yao
                                       University of Saskatchewan