42 lines
955 B
Python
42 lines
955 B
Python
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import numpy as np
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try:
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import mpmath
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except ImportError:
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pass
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def mpmath_wrightomega(x):
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return mpmath.lambertw(mpmath.exp(x), mpmath.mpf('-0.5'))
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def wrightomega_series_error(x):
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series = x
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desired = mpmath_wrightomega(x)
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return abs(series - desired) / desired
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def wrightomega_exp_error(x):
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exponential_approx = mpmath.exp(x)
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desired = mpmath_wrightomega(x)
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return abs(exponential_approx - desired) / desired
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def main():
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desired_error = 2 * np.finfo(float).eps
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print('Series Error')
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for x in [1e5, 1e10, 1e15, 1e20]:
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with mpmath.workdps(100):
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error = wrightomega_series_error(x)
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print(x, error, error < desired_error)
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print('Exp error')
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for x in [-10, -25, -50, -100, -200, -400, -700, -740]:
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with mpmath.workdps(100):
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error = wrightomega_exp_error(x)
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print(x, error, error < desired_error)
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if __name__ == '__main__':
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main()
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