29 lines
808 B
Python
29 lines
808 B
Python
#!/usr/bin/python3
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import math
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def bailey_borwein_plouffe_pi(n):
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"""
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See https://en.wikipedia.org/wiki/Approximations_of_%CF%80#Efficient_methods
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"""
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result = 0
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for k in range(n):
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result += (1/16)**k * ( 4/(8*k + 1) - 2/(8*k + 4) - 1/(8*k + 5) - 1/(8*k + 6))
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return result
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if( __name__ == "__main__"):
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assert bailey_borwein_plouffe_pi(1000) == math.pi
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# Please note that the ``is`` operator checks wether the
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# two references are the same object, basically by comparing
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# their pointers.
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#
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# The ``==`` operator accesses the ``__eq__`` method of the
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# object that *compares* the other object to itself.
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#
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# Because ``a/b`` **cannot** return the same object as ``math.pi``,
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# the latter was created when the module ``math`` was initialized,
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# this will **always** evaluate to False.
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