40 lines
962 B
Python
40 lines
962 B
Python
"""
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Statistics-related constants.
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"""
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import numpy as np
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# The smallest representable positive number such that 1.0 + _EPS != 1.0.
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_EPS = np.finfo(float).eps
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# The largest [in magnitude] usable floating value.
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_XMAX = np.finfo(float).max
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# The log of the largest usable floating value; useful for knowing
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# when exp(something) will overflow
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_LOGXMAX = np.log(_XMAX)
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# The smallest [in magnitude] usable (i.e. not subnormal) double precision
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# floating value.
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_XMIN = np.finfo(float).tiny
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# The log of the smallest [in magnitude] usable (i.e not subnormal)
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# double precision floating value.
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_LOGXMIN = np.log(_XMIN)
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# -special.psi(1)
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_EULER = 0.577215664901532860606512090082402431042
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# special.zeta(3, 1) Apery's constant
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_ZETA3 = 1.202056903159594285399738161511449990765
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# sqrt(pi)
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_SQRT_PI = 1.772453850905516027298167483341145182798
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# sqrt(2/pi)
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_SQRT_2_OVER_PI = 0.7978845608028654
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# log(sqrt(2/pi))
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_LOG_SQRT_2_OVER_PI = -0.22579135264472744
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