Lines Matching refs:Erf
26 // double erf(double x)
30 // erf(x) = --------- | exp(-t*t)dt
34 // erfc(x) = 1-erf(x)
36 // erf(-x) = -erf(x)
41 // erf(x) = x + x*R(x**2)
42 // erfc(x) = 1 - erf(x) if x in [-.84375,0.25]
47 // | R - (erf(x)-x)/x | <= 2
51 // erf(x) = (2/sqrt(pi))*(x - x**3/3 + x**5/10 - x**7/42 + ....)
55 // point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
57 // guarantee the error is less than one ulp for erf.
61 // erf(x) = sign(x) * (c + P1(s)/Q1(s))
64 // |P1/Q1 - (erf(|x|)-c)| <= 2**-59.06
66 // erf(1+s) = erf(1) + s*Poly(s)
69 // erf(1+s) - (c = (single)0.84506291151)
77 // erf(x) = 1 - erfc(x)
86 // erf(x) = sign(x)*(1.0 - erfc(x)) if x < 6, else
87 // erf(x) = sign(x)*(1.0 - tiny)
110 // erf(x) = sign(x) *(1 - tiny) (raise inexact)
115 // erf(0) = 0, erf(inf) = 1, erf(-inf) = -1,
117 // erfc/erf(NaN) is NaN
121 // Coefficients for approximation to erf in [0, 0.84375]
134 // Coefficients for approximation to erf in [0.84375, 1.25]
182 // Erf returns the error function of x.
185 // Erf(+Inf) = 1
186 // Erf(-Inf) = -1
187 // Erf(NaN) = NaN
188 func Erf(x float64) float64 {
