A* algorithm
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The document discusses finding the shortest route from Seri Tujuh Beach in Kelantan, Malaysia to Kuala Koh National Park using the A* search algorithm. It proposes using A* to search through places that could be visited along the way to determine the lowest total distance route. The document outlines estimating distances between locations, representing them on a map with symbols, building a search tree with A* calculations, and determining the shortest route and its total cost.
A* algorithm
- 1. Introduction In January 2014, Uitm student will start the semester break from 20 January until 20 February. We are a group of students are discussing to travel during our semester break. In order to make sure that we have enough time to travel, a proper strategy must be including in our preparation other than money. Our group have decided to visit Kelantan because there are more beautiful places there to be visited. The journey will start at Seri Tujuh Beach at Tumpat to the National Park at Kuala Koh. From the beach, we have to find the shortest route to save our time and arrived earlier to make other activities at Kuala Koh National Park. Our group discover for the route from the beach to the National Park through some others place to be visited. For examples, Kota Bharu Trade Centre, Bisikan Bayu Beach, Jeram Linang waterfall, Kelantan River, Stong mountain, Berangkat mountain and Cintawangsa mountain. The difficulty that we have to face is they want to still be able to generate the path with minimum cost. By choosing the best method, we will find the shortest route from Seri Tujuh beach to National Park. Objective The main objective of the project is to find the shortest distance to travel from Seri Tujuh beach to Kuala Koh National Park in Kelantan State.
- 2. Project scope Regarding to the problem that we face before, the suitable map was purposed to find the shortest distance. The project scope is in Malaysia which is Kelantan state. There are many places to be visited in Kelantan that we have discovered such as Kota Bharu Trade Centre, Bisikan Bayu Beach, Jeram Linang waterfall, Kelantan River, Stong Mountain, Berangkat Mountain and Cintawangsa Mountain. We need to pass through these places to arrive at our destination which is Kuala Koh National Park. We may visit the place that will consider the shortest distance for us to reach there. Then for the next other places to be visit, we also considered about the shortest distance. The places that will give the shortest distance from the place that we were located will be choosing.
- 3. Search method In order to find the shortest distance from Seri Tujuh beach to Kuala Koh National Park, the best method is by using A* algorithm. The method of A* algorithm is most famous solution for this problem. Generally, the solution is the most efficient used in most cases and give better implementation. A* algorithm was selected due to the important properties which is will always return the shortest path if a path exists to the destination. Other algorithms may find a path faster but it is not necessarily the "best" path we can take. A* uses a heuristic to search nodes considered more likely to lead to the destination first, allowing us to often find the best path without having to search the entire map and making the algorithm much faster. Other than that, A* is based on the idea that each node has some cost associated with it. If the costs for all nodes are the same then the best path returned by A* will also be the shortest path but A* can easily allow us to add different costs to moving through each node. This is because A* uses an optimistic estimate of the cost of a path through every node that it considers optimistic in that the true cost of a path through that node to the goal will be at least as great as the estimate. A* algorithm uses a best-first search and finds a least-cost path from a given initial node to one goal node. As A* algorithm traverses the tree, it follows a path of the lowest expected total cost or distance, keeping a sorted priority queue of alternate path segments along the way. Cost function of node n that denoted by f (n) is to determine the order in which the search visits nodes in the tree. The cost function ( f(n) = g(n) + h(n) ) is a sum of two functions which are the past path-cost function, which is the known distance from the starting node to the current node n denoted by g(n) and future path-cost function, which is an heuristic estimate of the distance from n to the goal denoted by h(n).
- 4. Proposed map Kelantan is rich Malay tourism centre with many beautiful places. In order to travel from one place to another place, we need to know about the distance. The route that we have to choose is started at Seri Tujuh beach and last with Kuala Koh National Park. The distance from each place to another place was obtained from google maps for the actual distance. To find the minimal cost which is shortest distance, the estimation distance from a place to the goal denoted by h (n) is needed. We have estimated about the distance from the place we are to reach at the goal. The places in the maps were denoted with the symbols. The distance to source node was set to 0, and the distances to all other nodes to infinity. The h (n) value and symbols of each places as followed:
- 5. Search tree The distance was calculated using A* algorithm formula which is f (n) = g (n) + h (n). G (n) refers to the distance travel from one place to another place and h (n) refers to the distance travel from one place to reach goal. The shortest distance that gives the smallest value was selected as the best solution. Below is the search tree for the maps from Seri Tujuh Beach to Kuala Koh National Park. Below is the search tree for the maps from Seri Tujuh Beach to Kuala Koh National Park.
- 6. Shortest route The proposed shortest route (with minimal cost) Cost of the route The proposed cost of the route (in related unit) Conclusion Reference http://en.wikipedia.org/wiki/A*_search_algorithm http://www.world-islam.com