Minor typos

[UbeCc]

There are duplicated comments mainly because of pasting code, where z-direction second is repeted.

  if (direction_switch) {
    //x-direction first
    semi_discrete_step( state , state     , state_tmp , dt / 3 , DIR_X , flux , tend );
    semi_discrete_step( state , state_tmp , state_tmp , dt / 2 , DIR_X , flux , tend );
    semi_discrete_step( state , state_tmp , state     , dt / 1 , DIR_X , flux , tend );
    //z-direction second
    semi_discrete_step( state , state     , state_tmp , dt / 3 , DIR_Z , flux , tend );
    semi_discrete_step( state , state_tmp , state_tmp , dt / 2 , DIR_Z , flux , tend );
    semi_discrete_step( state , state_tmp , state     , dt / 1 , DIR_Z , flux , tend );
  } else {
    //z-direction second
    semi_discrete_step( state , state     , state_tmp , dt / 3 , DIR_Z , flux , tend );
    semi_discrete_step( state , state_tmp , state_tmp , dt / 2 , DIR_Z , flux , tend );
    semi_discrete_step( state , state_tmp , state     , dt / 1 , DIR_Z , flux , tend );
    //x-direction first
    semi_discrete_step( state , state     , state_tmp , dt / 3 , DIR_X , flux , tend );
    semi_discrete_step( state , state_tmp , state_tmp , dt / 2 , DIR_X , flux , tend );
    semi_discrete_step( state , state_tmp , state     , dt / 1 , DIR_X , flux , tend );
  }