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44 lines
1.4 KiB
Python
44 lines
1.4 KiB
Python
__author__ = "Tobias Carryer"
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from time import time
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class LinearCongruentialGenerator:
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"""
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A pseudorandom number generator.
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"""
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# The default value for **seed** is the result of a function call which is not
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# normally recommended and causes ruff to raise a B008 error. However, in this case,
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# it is accptable because `LinearCongruentialGenerator.__init__()` will only be
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# called once per instance and it ensures that each instance will generate a unique
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# sequence of numbers.
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def __init__(self, multiplier, increment, modulo, seed=int(time())): # noqa: B008
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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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efficient 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
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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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