Added Breadth-First Tree Search

aimacode · norvig · Dec 20, 2017 · Dec 12, 2017 · Dec 16, 2017 · Dec 16, 2017
commit cd027d5498174b8b9ac251b5f6cdd057c0247514
diff --git a/gui/romania_problem.py b/gui/romania_problem.py
@@ -4,20 +4,28 @@
 import math
 sys.path.append(os.path.join(os.path.dirname(__file__), '..'))
 from search import *
-
+from search import breadth_first_tree_search as bfts
+from utils import Stack, FIFOQueue, PriorityQueue
+from copy import deepcopy
 root = None
 city_coord = {}
-romania_problem = GraphProblem('Arad', 'Bucharest', romania_map)
-algo=None
-start=None
-goal=None
+romania_problem = None
+algo = None
+start = None
+goal = None
+counter = -1
+city_map = None
+frontier = None
+front = None
+node = None
+next_button = None
 
 
 def create_map(root):
     '''
     This function draws out the required map.
     '''
-    global romania_problem
+    global city_map, start, goal
     romania_locations = romania_map.locations
     width = 750
     height = 670
@@ -237,6 +245,7 @@ def create_map(root):
 
     make_legend(city_map)
 
+
 def make_line(map, x0, y0, x1, y1, distance):
     '''
     This function draws out the lines joining various points.
@@ -263,47 +272,173 @@ def make_rectangle(map, x0, y0, margin, city_name):
         anchor=SE)
     city_coord.update({city_name: rect})
 
+
 def make_legend(map):
-    
-    rect1=map.create_rectangle(600,100,610,110,fill="white") 
-    text1 = map.create_text(615, 105,anchor=W,text="Un-explored")
-    
-    rect2=map.create_rectangle(600,115,610,125,fill="orange")
-    text2 = map.create_text(615, 120,anchor=W,text="Frontier")
-    
-    rect3=map.create_rectangle(600,130,610,140,fill="red")
-    text3 = map.create_text(615, 135,anchor=W,text="Currently Exploring")
-    
-    rect4=map.create_rectangle(600,145,610,155,fill="grey")
-    text4 = map.create_text(615, 150,anchor=W,text="Explored")
-    
-    rect5=map.create_rectangle(600,160,610,170,fill="dark green")
+
+    rect1 = map.create_rectangle(600, 100, 610, 110, fill="white")
+    text1 = map.create_text(615, 105, anchor=W, text="Un-explored")
+
+    rect2 = map.create_rectangle(600, 115, 610, 125, fill="orange")
+    text2 = map.create_text(615, 120, anchor=W, text="Frontier")
+
+    rect3 = map.create_rectangle(600, 130, 610, 140, fill="red")
+    text3 = map.create_text(615, 135, anchor=W, text="Currently Exploring")
+
+    rect4 = map.create_rectangle(600, 145, 610, 155, fill="grey")
+    text4 = map.create_text(615, 150, anchor=W, text="Explored")
+
+    rect5 = map.create_rectangle(600, 160, 610, 170, fill="dark green")
     text5 = map.create_text(615, 165, anchor=W, text="Final Solution")
-
+
+
+def tree_search(problem):
+    '''
+    This function has been changed to make it suitable for the Tkinter GUI.
+    '''
+    global counter, frontier, node
+    # print(counter)
+    if counter == -1:
+        frontier.append(Node(problem.initial))
+        # print(frontier)
+        display_frontier(frontier)
+    if counter % 3 == 0 and counter >= 0:
+        node = frontier.pop()
+        # print(node)
+        display_current(node)
+    if counter % 3 == 1 and counter >= 0:
+        if problem.goal_test(node.state):
+            # print(node)
+            return node
+        frontier.extend(node.expand(problem))
+        # print(frontier)
+        display_frontier(frontier)
+    if counter % 3 == 2 and counter >= 0:
+        # print(node)
+        display_explored(node)
+    return None
+
+
+def display_frontier(queue):
+    '''
+    This function marks the frontier nodes (orange) on the map.
+    '''
+    global city_map, city_coord
+    qu = deepcopy(queue)
+    while qu:
+        node = qu.pop()
+        for city in city_coord.keys():
+            if node.state == city:
+                city_map.itemconfig(city_coord[city], fill="orange")
+    return
+
+
+def display_current(node):
+    '''
+    This function marks the currently exploring node (red) on the map.
+    '''
+    global city_map, city_coord
+    city = node.state
+    city_map.itemconfig(city_coord[city], fill="red")
+    return
+
+
+def display_explored(node):
+    '''
+    This function marks the already explored node (gray) on the map.
+    '''
+    global city_map, city_coord
+    city = node.state
+    city_map.itemconfig(city_coord[city], fill="gray")
+    return
+
+
+def display_final(cities):
+    '''
+    This function marks the final solution nodes (green) on the map.
+    '''
+    global city_map, city_coord
+    for city in cities:
+        city_map.itemconfig(city_coord[city], fill="green")
+    return
+
+
+def breadth_first_tree_search(problem):
+    """Search the shallowest nodes in the search tree first."""
+    global frontier, counter
+    if counter == -1:
+        frontier = FIFOQueue()
+    return tree_search(problem)
+
+
+def on_click():
+    '''
+    This function defines the action of the 'Next' button.
+    '''
+    global algo, counter, next_button, romania_problem, start, goal
+    romania_problem = GraphProblem(start.get(), goal.get(), romania_map)
+    if "Breadth-First Tree Search" == algo.get():
+        node = breadth_first_tree_search(romania_problem)
+        if node is not None:
+            final_path = bfts(romania_problem).solution()
+            final_path.append(start.get())
+            display_final(final_path)
+            next_button.config(state="disabled")
+        counter += 1
+
+
+def reset_map():
+    global counter, city_coord, city_map, next_button
+    counter = -1
+    for city in city_coord.keys():
+        city_map.itemconfig(city_coord[city], fill="white")
+    next_button.config(state="normal")
+
+# TODO: Add more search algorithms in the OptionMenu
+
+
 def main():
-    global algo,start,goal
+    global algo, start, goal, next_button
     root = Tk()
     root.title("Road Map of Romania")
     root.geometry("950x1150")
-    algo=StringVar(root)
+    algo = StringVar(root)
     start = StringVar(root)
     goal = StringVar(root)
-    algo.set("Breadth First Tree Search")
+    algo.set("Breadth-First Tree Search")
     start.set('Arad')
     goal.set('Bucharest')
-    cities=list(romania_map.locations.keys())
-    cities.sort()
-    algorithm_menu=OptionMenu(root,algo,"Breadth-First Tree Search","Depth-First Tree Search")
-    Label(root,text="\n Search Algorithm").pack()
+    cities = sorted(romania_map.locations.keys())
+    algorithm_menu = OptionMenu(root, algo, "Breadth-First Tree Search")
+    Label(root, text="\n Search Algorithm").pack()
     algorithm_menu.pack()
-    Label(root,text="\n Start City").pack()
-    start_menu = OptionMenu(root,start,*cities)
+    Label(root, text="\n Start City").pack()
+    start_menu = OptionMenu(root, start, *cities)
     start_menu.pack()
     Label(root, text="\n Goal City").pack()
-    goal_menu = OptionMenu(root,goal,*cities)
+    goal_menu = OptionMenu(root, goal, *cities)
     goal_menu.pack()
-    next_button = Button(root, width=6, height=2, text="Next", command=None,padx=2,pady=2,relief=GROOVE)
-    next_button.pack(side=BOTTOM)
+    frame1 = Frame(root)
+    next_button = Button(
+        frame1,
+        width=6,
+        height=2,
+        text="Next",
+        command=on_click,
+        padx=2,
+        pady=2,
+        relief=GROOVE)
+    next_button.pack(side=RIGHT)
+    reset_button = Button(
+        frame1,
+        width=6,
+        height=2,
+        text="Reset",
+        command=reset_map,
+        padx=2,
+        pady=2,
+        relief=GROOVE)
+    reset_button.pack(side=RIGHT)
+    frame1.pack(side=BOTTOM)
     create_map(root)
     root.mainloop()