65 lines
2.3 KiB
Python
65 lines
2.3 KiB
Python
"""
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This module holds the logic for the solving
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"""
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class Dijkstra():
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def __init__(self, graph: dict, connection: tuple):
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"""
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table: matrix with vertex as key, price and prev vertex as value
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OL: open list, to keep track of finished vertecis
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"""
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self.graph = graph
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self.table = {}
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for vertex in graph:
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self.table.update({vertex: {
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"distance": (9999999, 999999),
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"prev": None}})
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self.table[connection[0]]["distance"] = (0, 0)
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def algorithm(self, switch: str):
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assert(switch == "time" or switch == "co2")
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print("Performing Dijkstra on the following graph...")
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for vertex in self.graph:
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print(f"{vertex}: {self.graph[vertex]}")
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print("")
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for v1 in self.graph.keys():
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neighbors = self.graph[v1]
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for n in neighbors:
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key = [elem for elem in n.keys()][0] # name of neighbor node
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edge = (n[key]["time"], n[key]["co2"])
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# update both time and co2
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time = self.table[v1]["distance"][0] + edge[0]
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co2 = self.table[v1]["distance"][1] + edge[1]
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# but only eval the one we want
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if switch == "time":
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if time < self.table[key]["distance"][0]:
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self.table[key]["distance"] = (time, co2)
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self.table[key]["prev"] = v1
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elif switch == "co2":
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if co2 < self.table[key]["distance"][1]:
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self.table[key]["distance"] = (time, co2)
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self.table[key]["prev"] = v1
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print("Final Dijkstra table:", self.table)
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def print_result(self, connection: tuple):
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sequence = []
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(start, dest) = connection
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# start at destination
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sequence.append(dest)
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# go through all possibilities until we're back at start
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while start not in sequence:
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current = self.table[sequence[-1]] # last element of list
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prev = current["prev"]
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sequence.append(prev)
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sequence.reverse()
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print(sequence)
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print("Total Time:", self.table[dest]["distance"][0])
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print("Total CO2:", self.table[dest]["distance"][1])
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