""" | |
Statistics-related constants. | |
""" | |
import numpy as np | |
# The smallest representable positive number such that 1.0 + _EPS != 1.0. | |
_EPS = np.finfo(float).eps | |
# The largest [in magnitude] usable floating value. | |
_XMAX = np.finfo(float).max | |
# The log of the largest usable floating value; useful for knowing | |
# when exp(something) will overflow | |
_LOGXMAX = np.log(_XMAX) | |
# The smallest [in magnitude] usable (i.e. not subnormal) double precision | |
# floating value. | |
_XMIN = np.finfo(float).tiny | |
# The log of the smallest [in magnitude] usable (i.e not subnormal) | |
# double precision floating value. | |
_LOGXMIN = np.log(_XMIN) | |
# -special.psi(1) | |
_EULER = 0.577215664901532860606512090082402431042 | |
# special.zeta(3, 1) Apery's constant | |
_ZETA3 = 1.202056903159594285399738161511449990765 | |
# sqrt(pi) | |
_SQRT_PI = 1.772453850905516027298167483341145182798 | |
# sqrt(2/pi) | |
_SQRT_2_OVER_PI = 0.7978845608028654 | |
# log(pi) | |
_LOG_PI = 1.1447298858494002 | |
# log(sqrt(2/pi)) | |
_LOG_SQRT_2_OVER_PI = -0.22579135264472744 | |