astar - graph search

1 files changed, 32 insertions, 0 deletions

diff --git a/search/atar_demo.py b/search/atar_demo.py
new file mode 100644
index 0000000..a32af92
--- /dev/null
+++ b/search/atar_demo.py
@@ -0,0 +1,32 @@
+
+import astar
+
+
+class GraphAStar(astar.AStar):
+    def __init__(self, nodes):
+        self.nodes = nodes
+
+    def neighbors(self, node):
+        for n, d in self.nodes[node]:
+            yield n
+
+    # g function
+    def distance_between(self, n1, n2):
+        for n, d in self.nodes[n1]:
+            if n == n2:
+                return d
+
+    # h function
+    def heuristic_cost_estimate(self, current, goal):
+        return 1
+
+
+if __name__ == '__main__':
+    nodes = {'A': [('B', 100), ('C', 20)],
+             'C': [('D', 20)],
+             'D': [('B', 20)]}
+    # A -> B
+
+    graph_solver = GraphAStar(nodes)
+    print(list(graph_solver.astar('A', 'B')))
+    print(list(graph_solver.astar('A', 'C')))