释义 |
ErfThe ``error function'' encountered in integrating the Gaussian Distribution.
where Erfc is the complementary error function and is the incomplete Gamma Function. It canalso be defined as a Maclaurin Series
 | (4) |
Erf has the values
It is an Odd Function
 | (7) |
and satisfies
 | (8) |
Erf may be expressed in terms of a Confluent Hypergeometric Function of the First Kind as
 | (9) |
Erf is bounded by
 | (10) |
Its Derivative is
 | (11) |
where is a Hermite Polynomial. The first Derivative is
 | (12) |
and the integral is
 | (13) |
For , erf may be computed from
(Acton 1990). For ,
Using Integration by Parts gives
so
 | (20) |
and continuing the procedure gives the Asymptotic Series
 | (21) |
A Complex generalization of is defined as
See also Dawson's Integral,Erfc, Erfi, Gaussian Integral, Normal Distribution Function, Probability Integral References
Abramowitz, M. and Stegun, C. A. (Eds.). ``Error Function'' and ``Repeated Integrals of the Error Function.'' §7.1-7.2 in Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, pp. 297-300, 1972.Acton, F. S. Numerical Methods That Work, 2nd printing. Washington, DC: Math. Assoc. Amer., p. 16, 1990. Arfken, G. Mathematical Methods for Physicists, 3rd ed. Orlando, FL: Academic Press, pp. 568-569, 1985. Spanier, J. and Oldham, K. B. ``The Error Function and Its Complement .'' Ch. 40 in An Atlas of Functions. Washington, DC: Hemisphere, pp. 385-393, 1987. |