Lines Matching refs:erf
27 /* double erf(double x)
31 * erf(x) = --------- | exp(-t*t)dt
35 * erfc(x) = 1-erf(x)
37 * erf(-x) = -erf(x)
42 * erf(x) = x + x*R(x^2)
43 * erfc(x) = 1 - erf(x) if x in [-.84375,0.25]
46 * erf(x) = (2/sqrt(pi))*(x - x^3/3 + x^5/10 - x^7/42 + ....)
50 * point of erf(x) is near 0.6174 (i.e., erf(x)=x when x is
52 * guarantee the error is less than one ulp for erf.
56 * erf(x) = sign(x) * (c + P1(s)/Q1(s))
60 * erf(1+s) = erf(1) + s*Poly(s)
67 * erf(x) = 1 - erfc(x)
75 * erf(x) = sign(x)*(1.0 - erfc(x)) if x < 6.666, else
76 * erf(x) = sign(x)*(1.0 - tiny)
90 * erf(x) = sign(x) *(1 - tiny) (raise inexact)
95 * erf(0) = 0, erf(inf) = 1, erf(-inf) = -1,
97 * erfc/erf(NaN) is NaN
106 return erf(x);
117 * Coefficients for approximation to erf on [0,0.84375]
140 * Coefficients for approximation to erf in [0.84375,1.25]
142 /* erf(x+1) = 0.845062911510467529296875 + pa(x)/qa(x)
294 /* erf(nan)=nan, erf(+-inf)=+-1 */
347 return erf(x);