FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 FIRST_RK_STEP_PART2 INITIALIZE_STOCH