do k=1,9 e_k(1) = real(e((k-1)*2+1)) e_k(2) = real(e((k-1)*2+2)) DP = e_k(1)*U_x(i,j) + e_k(2)*U_y(i,j) f_eq = w(k)*rho(i,j)*(1.0+3.0*DP+(9.0/2.0)*(DP**2.0)-(3.0/2.0)*DPU) f(i,j,k)=f(i,j,k)-(1.0/tau)*(f(i,j,k)-f_eq) enddo