#--------------------------------------------------------------------------
  # * Maximum Z value of all instance variables
  #--------------------------------------------------------------------------
  def z_max
    output = []
    # Passes Through All Instance Variables
    self.instance_variables.each do |object_name|
      # Evaluates Object
      object = eval object_name
      # Find the z value
      output += z_value(object)
    end
    # Returns max z value
    return output.nitems > 0 ? output.compact.max : 0
  end
  #--------------------------------------------------------------------------
  # * Minimum Z value of all instance variables
  #--------------------------------------------------------------------------
  def z_min
    output = []
    # Passes Through All Instance Variables
    self.instance_variables.each do |object_name|
      # Evaluates Object
      object = eval object_name
      # Find the z value
      output += z_value(object)
    end
    # Returns min z value
    return output.nitems > 0 ? output.compact.min : 0
  end
  #--------------------------------------------------------------------------
  # * Find Z value of an object; recursive for hashes and arrays - Returns Array
  #--------------------------------------------------------------------------
  def z_value(object)
    output = []
    # Stop Processing If Responds to Disposed? && is Disposed
    return output if (object.respond_to?(:disposed?) && object.disposed?)
    # If Hash
    if object.is_a? Hash
      # Pass through all keys and values
      object.each {|key, value| output += z_value(key) + z_value(value)}
    elsif object.is_a?(Array) # If Array
      # Passes through all object
      object.each {|obj| output += z_value(obj)}
    elsif object.respond_to?(:z) and object.z.kind_of?(Numeric)
      output.push(object.z)
    end
    return output
  end

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