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34 lines
1.1 KiB
Python
34 lines
1.1 KiB
Python
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__author__ = "Tobias Carryer"
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from time import time
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class LinearCongruentialGenerator(object):
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"""
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A pseudorandom number generator.
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"""
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def __init__( self, multiplier, increment, modulo, seed=int(time()) ):
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"""
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These parameters are saved and used when nextNumber() is called.
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modulo is the largest number that can be generated (exclusive). The most
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efficent values are powers of 2. 2^32 is a common value.
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"""
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self.multiplier = multiplier
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self.increment = increment
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self.modulo = modulo
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self.seed = seed
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def next_number( self ):
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"""
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The smallest number that can be generated is zero.
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The largest number that can be generated is modulo-1. modulo is set in the constructor.
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"""
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self.seed = (self.multiplier * self.seed + self.increment) % self.modulo
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return self.seed
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if __name__ == "__main__":
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# Show the LCG in action.
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lcg = LinearCongruentialGenerator(1664525, 1013904223, 2<<31)
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while True :
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print lcg.next_number()
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