subroutine getdet(add,ideter)
    use iso_c_binding
    implicit none
    BEGIN_DOC
    ! this routing gives the determinant in
    ! the traditional form given its address
    END_DOC
    integer,INTENT(INOUT)::ideter(natomax)
    integer(C_SIZE_T),INTENT(IN)::add
    integer(C_SIZE_T)::deta,detb
    integer::i,const,ia,ib, natom2

    ib = MOD(add,nt2)
    if(MOD(add,nt2).eq.0)then
        ib=nt2
    endif
    ia = (add-ib)/nt2
    ia = nt1 - ia
    ideter=1
    const=0
    detb=0
    deta=0
    i=1
    detb = det(ib,1)
    deta = deth(ia,1)
    if(FAM1) then
      if(fix_trou1 .eq. fix_trou2) then
          deta = ISHFT(deta,-(natom/2))
      else
          natom2 = natom - (fix_trou2 - fix_trou1)
          deta = ISHFT(deta, -natom2)
      endif
    endif
!    do while (i.le.(ib))
!        const=1
!        do while(popcnt(detb).ne.nbeta .or. const==1)
!            detb+=1
!            const=0
!        enddo
!        i+=1
!        write(6,14)detb,detb
!    enddo
!    i=1
!    do while (i.le.(ia))
!        const=1
!        do while(popcnt(deta).ne.ntrou .or. const==1)
!            deta+=1
!            const=0
!        enddo
!        i+=1
!        write(6,14)deta,deta
!    enddo
    if(FAM1) then
        if(fix_trou1 .eq. fix_trou2) then
            natom2 = natom/2
        else
            natom2 = (fix_trou2 - fix_trou1)
        endif
    else
        natom2 = natom
    endif

    do i=0,(natom2) - 1
        if(BTEST(deta,i))then
            ideter((natom2)-i)=3
        endif
    enddo
!   do i=ib-2,ib+2
!     print *,i," det=",det(i,1)," add=",det(i,2)
!   enddo
!   print *,"add=",ib," detb=",detb
!   write(6,*)(ideter(i),i=1,natom)
    const=0
    do i=0,natom-1
        if(ideter(natom-i).eq.1)then
            if(BTEST(detb,const))then
                ideter(natom-i)=2
            endif
            const=const+1
        endif
    enddo

return
10  FORMAT(B64,I8,F8.2)
15  FORMAT(B64,I8,I8,I8)
11  FORMAT(B64,I3,B64)
12  FORMAT(I5,$)
13  FORMAT(B64,B64)
14  FORMAT(B64,I8)
16  FORMAT(B64,I8,I8)
end subroutine getdet