Menu
Which should be the way to get a simple implementation of A* (A star) algorithm in C#?
457
The closed list is a collection of all expanded nodes. This means that those are nodes that were already "searched". This prevents the search from visiting nodes again and again. A side note: in big domains, the closed list can't fit all nodes, so the closed list has to be implemented smartly.
ALGORITHMS - A* Algorithm A* is a best-first search algorithm that relies on an open list and a closed list to find a path that is both optimal and complete towards the goal. It works by combining the benefits of the uniform-cost search and greedy search algorithms.
The A* Algorithm Like Dijkstra, A* works by making a lowest-cost path tree from the start node to the target node. What makes A* different and better for many searches is that for each node, A* uses a function f ( n ) f(n) f(n) that gives an estimate of the total cost of a path using that node.
A* is complete and will always find a solution if one exists. Have a look at the wikipedia article. If further the heuristics is admissible and monotonic the algorithm will also be admissible(i.e. optimal).
The implementation of A* Algorithm involves maintaining two lists- OPEN and CLOSED. OPEN contains those nodes that have been evaluated by the heuristic function but have not been expanded into successors yet. CLOSED contains those nodes that have already been visited.
Specifically, A* selects the path that minimizes h(n) = a heuristic function that estimates the cost of the cheapest path from n to the goal Now you will see algorithm of A* algorithm. 1. GENERATE A LIST of all possible next steps 2. STORE CHILDREN in priority queue 3. SELECT CLOSEST child and REPEAT until goal reached or no more children
Select Algorithm: Select the algorithm that you want to implement from scratch. Be as specific as possible. This means not only the class, and type of algorithm, but also go as far as selecting a specific description or implementation that you want to implement.
A* Algorithm in Artificial Intelligence is a popular path finding technique. A* Algorithm Working & Pseudo Code. A* Algorithm Examples in AI. A* Algorithm on 8 Puzzle Problem is discussed.
This article explains the basic implementation in length:
The goal of this blog post is to show the fundamentals of A* through a really simple C# implementation.
It also points to better implementations, more suitable for production use:
As for ways to find better routes, there are plenty of C# examples around that are far better and richer than this one. CastorTiu has a really nice demo solution on CodeProject, A* algorithm implementation in C#, that animates the search algorithm and allows the user to tweak a few settings. [...]
EpPathFinding.cs- A Fast Path Finding Algorithm (Jump Point Search) in C# (grid-based). It has a nice, clear GUI and allows a few settings to be tweaked.
167
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
