anchor.diff:          le=fstrMAT%indexL_lagrange(ilag)
           do l=ls,le
             j=fstrMAT%itemL_lagrange(l)
  -          ks=hecMATLag%indexL(i-1)+1
  -          ke=hecMATLag%indexL(i)
  -          do k = ks, ke
  +          do k = idx_lag_s, idx_lag_e
               if (hecMATLag%itemL(k) < j) cycle
               if (hecMATLag%itemL(k) > j) cycle
               !if (hecMATLag%itemL(k) /= j) stop 'ERROR itemL j'
  
positive.code:       if (fg_eliminate) then
          call solve_eliminate(hecMESH, hecMAT, fstrMAT)
        else
          call solve_no_eliminate(hecMESH, hecMAT, fstrMAT)
        endif
      endif
  
  
negative.code:         jb_lag = (j+2)/3
          iwUc(jb_lag) = 1
        enddo
        idx_lag_s = idx
        do j=1,nb_lag
          if (iwUc(j) > 0) then
            hecMATLag%itemU(idx) = hecMAT%N + j
            idx = idx + 1
          endif
        enddo
        idx_lag_e = idx - 1
        ! Lag. AU
        ls=fstrMAT%indexU_lagrange(i-1)+1
        le=fstrMAT%indexU_lagrange(i)
  