anchor.diff:  
          !! Energy value based convergence
          energy_value2 = energy_value
  -       energy_value = 2.0_NTREAL*DotDistributedSparseMatrix(X_k, WorkingHamiltonian)
  +       energy_value = 2.0_NTREAL*DotDistributedSparseMatrix(X_k, &
  +            & WorkingHamiltonian)
          norm_value = ABS(energy_value - energy_value2)
   
          IF (solver_parameters%be_verbose) THEN
  
positive.code:     !! Compute alpha
      alpha1 = nel*0.5_NTREAL/(e_max-lambda)
      alpha2 = (X_k%actual_matrix_dimension-nel*0.5_NTREAL)/(lambda-e_min)
      alpha = min(alpha1,alpha2)
  
      factor = -alpha/X_k%actual_matrix_dimension
  
  
negative.code:                 zero_value = zero_value*zero_value
               ELSE
                  tempfx = (zero_value*zero_value) &
                       & * (4.0_NTREAL*zero_value - &
                       & 3.0_NTREAL*zero_value*zero_value)
                  tempgx = (zero_value*zero_value) * (1.0_NTREAL-zero_value) &
                       & * (0.0_NTREAL-zero_value)
                  zero_value = tempfx + sigma_array(inner_counter)*tempgx
               END IF
            END DO polynomial
  