dEnergy.f

      real*8 function dEnergy(
     1       lattype, L, L_p,       
     2       nnnumber, nnnum_p,       
     3       idx, jdy,
     4       V2, V1, erko, T,    
     5       ijatom,i,j  ) 
       integer lattype, L, L_p,nnnumber, nnnum_p
       integer idx(nnnum_p), jdy(nnnum_p) 
       real*8  V2, V1, erko, T, dE2, dE1
       integer idE2, inE2
       integer ijatom(0:L_p+1,0:L_p+1)
       integer i,j       
       integer k,i2,j2
       
        dE1=-2*ijatom(i,j)*V1+2*ijatom(i,j)*erko*T
       
         inE2=0 
         do 33 k=1,nnnumber
           i2=i+idx(k)
           j2=j+jdy(k)
           inE2=inE2+ijatom(i2,j2)
33       continue           
         idE2=-2*ijatom(i,j)*inE2   
        dE2=V2*idE2
       dEnergy=dE1+dE2
c      WRITE(*,*) 'Erko je',erko
      end