41 lines
1.2 KiB
Python
41 lines
1.2 KiB
Python
# Copyright 2018 AWCloud Software Co., Ltd
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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# Codes are from https://www.craig-wood.com/nick/articles/pi-machin/
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def arctan_euler(x, one):
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x_squared = x * x
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x_squared_plus_1 = x_squared + 1
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term = (x * one) // x_squared_plus_1
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total = term
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two_n = 2
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while True:
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divisor = (two_n + 1) * x_squared_plus_1
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term *= two_n
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term = term // divisor
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if term == 0:
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break
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total += term
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two_n += 2
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return total
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def pi_machin(one):
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return 4 * (4 * arctan_euler(5, one) - arctan_euler(239, one))
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def main(digit=50000, *args, **kwargs):
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return str(pi_machin(10**digit))[:15]
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