Single Step Mode
The Single Step Mode allows you to trace the execution of any of the available search methods. A floating algorithm window showing corresponding steps during the animation can optionally be displayed. Controls for this are available under the Settings menu. You may select this mode from the Mode menu. Once you have selected a search method from the Algorithm menu (and a heuristic also in the case of the heuristic searches, to be considered later in the course materials) then you may begin the animation by clicking on the Start button. This mode requires you use the Next button to control the progression of the algorithm. When you have finished you may click the Reset button and then make different problem, algorithm, or mode settings. Each node in the search tree presents a 8-Puzzle game board state. The position of the tiles on the board is depicted. The numbers immediately beneath the game tiles represent g(), the cost so far, and h() the heuristic estimated remaining cost to the goal state. For non-heuristic searches like Depth-First and Breath-First these values will be the level number and zero respectively. The number on the bottom row of each node represents the expansion number for that node. ie. the order in which the nodes were examined. Repeat states and unexplored states will have an expansion number of zero. The colours used to depict the nodes in the search tree represent the major data structures used by all search methods. In the example above, blue represents nodes in the closed list. Yellow represents nodes in the open list, and Green represents the node from the open list that the search method will chose to expand next.

Copyright © 1999. Department of Computer Science, RMIT University. Last Modified: 17th June, 1999.

Single Step Mode

The Single Step Mode allows you to trace the execution of any of the available search methods. A floating algorithm window showing corresponding steps during the animation can optionally be displayed. Controls for this are available under the Settings menu.

You may select this mode from the Mode menu.

Once you have selected a search method from the Algorithm menu (and a heuristic also in the case of the heuristic searches, to be considered later in the course materials) then you may begin the animation by clicking on the Start button.

This mode requires you use the Next button to control the progression of the algorithm.

When you have finished you may click the Reset button and then make different problem, algorithm, or mode settings.

Each node in the search tree presents a 8-Puzzle game board state. The position of the tiles on the board is depicted. The numbers immediately beneath the game tiles represent g(), the cost so far, and h() the heuristic estimated remaining cost to the goal state. For non-heuristic searches like Depth-First and Breath-First these values will be the level number and zero respectively. The number on the bottom row of each node represents the expansion number for that node. ie. the order in which the nodes were examined. Repeat states and unexplored states will have an expansion number of zero.

The colours used to depict the nodes in the search tree represent the major data structures used by all search methods. In the example above, blue represents nodes in the closed list. Yellow represents nodes in the open list, and Green represents the node from the open list that the search method will chose to expand next.