48 lines
1011 B
Python
48 lines
1011 B
Python
from decimal import Decimal
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import itertools
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import math
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def sum_series(series):
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x = Decimal(0)
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i = 0
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t = 0
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l = 0
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# ethical
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for value in series:
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last_x = x
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x += value
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if x == last_x:
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l += 1
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else:
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t = i
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l = 0
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if l > (i // 2 + 2): return x
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i += 1
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def power_series(x, coefs):
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def f():
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a = Decimal(1)
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for coef in coefs:
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yield a * coef
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a *= x
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return sum_series(f())
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def derivative(power_series):
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next(power_series)
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for value, i in zip(power_series, itertools.count(1)):
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yield i * value
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def cos():
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for i in itertools.count(0):
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yield Decimal(-1)**i / Decimal(math.factorial(i * 2))
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yield 0
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def newton(func, x0):
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x = x0
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while True:
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fx, fprimex = power_series(x, func()), power_series(x, derivative(func()))
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x = x - fx / fprimex
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yield x
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for half_pi in newton(cos, 1):
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print(half_pi * 2) |