anchor.diff:            zero_value = midpoint
             !! Compute polynomial function at the guess point.
             polynomial:DO inner_counter=1,total_iterations
  -             zero_value = zero_value + 2.0_NTREAL*((zero_value*zero_value)*(1.0_NTREAL-zero_value) &
  -                          & - sigma_array(inner_counter)*(zero_value*(1.0_NTREAL-zero_value)))
  +             zero_value = zero_value + &
  +                  & 2.0_NTREAL*((zero_value*zero_value)*(1.0_NTREAL-zero_value)&
  +                  & - sigma_array(inner_counter)* &
  +                  & (zero_value*(1.0_NTREAL-zero_value)))
             END DO polynomial
             !! Change bracketing.
             IF (zero_value .LT. 0.5_NTREAL) THEN
  
positive.code:              interval_b = midpoint
            END IF
            !! Check convergence.
            IF ( ABS(zero_value-0.5_NTREAL) .LT. solver_parameters%converge_diff ) THEN
               EXIT
            END IF
         END DO midpoints
  
negative.code: 
         !! Energy value based convergence
         energy_value2 = energy_value
         energy_value = 2.0_NTREAL*DotDistributedSparseMatrix(D1, &
              & WorkingHamiltonian)
         norm_value = ABS(energy_value - energy_value2)
  
         IF (solver_parameters%be_verbose) THEN
  