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72 lines
1.6 KiB
Python
72 lines
1.6 KiB
Python
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'''
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Author: https://github.com/bhushan-borole
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'''
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'''
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The input graph for the algorithm is:
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A B C
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A 0 1 1
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B 0 0 1
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C 1 0 0
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'''
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graph = [[0, 1, 1],
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[0, 0, 1],
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[1, 0, 0]]
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class Node:
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def __init__(self, name):
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self.name = name
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self.inbound = []
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self.outbound = []
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def add_inbound(self, node):
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self.inbound.append(node)
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def add_outbound(self, node):
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self.outbound.append(node)
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def __repr__(self):
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return 'Node {}: Inbound: {} ; Outbound: {}'.format(self.name,
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self.inbound,
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self.outbound)
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def page_rank(nodes, limit=3, d=0.85):
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ranks = {}
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for node in nodes:
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ranks[node.name] = 1
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outbounds = {}
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for node in nodes:
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outbounds[node.name] = len(node.outbound)
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for i in range(limit):
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print("======= Iteration {} =======".format(i+1))
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for j, node in enumerate(nodes):
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ranks[node.name] = (1 - d) + d * sum([ ranks[ib]/outbounds[ib] for ib in node.inbound ])
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print(ranks)
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def main():
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names = list(input('Enter Names of the Nodes: ').split())
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nodes = [Node(name) for name in names]
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for ri, row in enumerate(graph):
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for ci, col in enumerate(row):
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if col == 1:
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nodes[ci].add_inbound(names[ri])
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nodes[ri].add_outbound(names[ci])
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print("======= Nodes =======")
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for node in nodes:
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print(node)
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page_rank(nodes)
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if __name__ == '__main__':
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main()
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