code: def round(self, value_array):
          
          value = value_array[0]
          rounded_value = self.domain[0]
  
          for domain_value in self.domain:
              if np.abs(domain_value - value) < np.abs(rounded_value - value):
                  rounded_value = domain_value
  
          return [rounded_value]
docs: Rounds a discrete variable by selecting the closest point in the domain
          Assumes an 1d array with a single element as an input.