text: #ifndef STEP_SIZE_ADDITIVE 
  #define STEP_SIZE_ADDITIVE
  
  #include "StepSize.h"
  
  class Derivative;
  
  /** \brief This class implements step size calculation in the case when 
  	additive path cost function is used.
  */
  class StepSizeAdd : public StepSize {
  	public:
  		StepSizeAdd(LineSearch *lineSearch, Derivative *der);
  		~StepSizeAdd();
  		
  		void initialiseDerivative(DescDirection *algo);
  	private:
  		Derivative *der_;
  };
  
  #endif
  