For , (11) (12) Using integration by parts gives (13) (14) (15) (16) so (17) and continuing the procedure gives the asymptotic series (18) (19) (20) (OEIS A001147 and A000079). Both functions are overloaded to accept arguments of type float, double, and long double. The system returned: (22) Invalid argument The remote host or network may be down. When the error function is evaluated for arbitrary complex arguments z, the resulting complex error function is usually discussed in scaled form as the Faddeeva function: w ( z ) =

Please try the request again. M. and Watson, G.N. I did not know about the entropy-power inequality, so, thank you for adding that tool to my arsenal! –M.B.M.

p.297. Acton, F.S. MR0167642. Related functions[edit] The error function is essentially identical to the standard normal cumulative distribution function, denoted Φ, also named norm(x) by software languages, as they differ only by scaling and translation.

Perl: erf (for real arguments, using Cody's algorithm[20]) is implemented in the Perl module Math::SpecFun Python: Included since version 2.7 as math.erf() and math.erfc() for real arguments. Washington, DC: Hemisphere, pp.385-393, 1987. How to use the binomial theorem to calculate binomials with a negative exponent Can Communism become a stable economic strategy? Generalized error functions[edit] Graph of generalised error functions En(x): grey curve: E1(x) = (1−e−x)/ π {\displaystyle \scriptstyle {\sqrt {\pi }}} red curve: E2(x) = erf(x) green curve: E3(x) blue curve: E4(x)

Online Integral Calculator» Solve integrals with Wolfram|Alpha. Erf has the values (21) (22) It is an odd function (23) and satisfies (24) Erf may be expressed in terms of a confluent hypergeometric function of the first kind as The system returned: (22) Invalid argument The remote host or network may be down. The error function at +∞ is exactly 1 (see Gaussian integral).

Despite the name "imaginary error function", erfi ( x ) {\displaystyle \operatorname 8 (x)} is real when x is real. The antiderivative of $e^{-t^2}$ is not $\frac{-1}{2t} e^{-t^2}$. –Rahul Sep 10 '11 at 5:41 3 @Angela, at the very least, it would be good of you to rewrite what you've Arfken, G. A complex generalization of is defined as (39) (40) Integral representations valid only in the upper half-plane are given by (41) (42) SEE ALSO: Dawson's Integral, Erfc, Erfi, Fresnel Integrals, Gaussian

Springer-Verlag. These generalised functions can equivalently be expressed for x>0 using the Gamma function and incomplete Gamma function: E n ( x ) = 1 π Γ ( n ) ( Γ IEEE Transactions on Wireless Communications, 4(2), 840–845, doi=10.1109/TWC.2003.814350. ^ Chang, Seok-Ho; Cosman, Pamela C.; Milstein, Laurence B. (November 2011). "Chernoff-Type Bounds for the Gaussian Error Function". Does anyone know if this is solvable?

What is the first movie to show this hard work message at the very end? Despite the name "imaginary error function", erfi ( x ) {\displaystyle \operatorname 8 (x)} is real when x is real. New York: Dover, pp.297-309, 1972. H.

Thank you all for your help with this! –M.B.M. When the error function is evaluated for arbitrary complex arguments z, the resulting complex error function is usually discussed in scaled form as the Faddeeva function: w ( z ) = Generalized error functions[edit] Graph of generalised error functions En(x): grey curve: E1(x) = (1−e−x)/ π {\displaystyle \scriptstyle {\sqrt {\pi }}} red curve: E2(x) = erf(x) green curve: E3(x) blue curve: E4(x) Math.

For complex

Generated Mon, 17 Oct 2016 03:52:32 GMT by s_wx1131 (squid/3.5.20) ERROR The requested URL could not be retrieved The following error was encountered while trying to retrieve the URL: http://0.0.0.9/ Connection Sep 12 '11 at 0:13 | show 1 more comment 2 Answers 2 active oldest votes up vote 10 down vote accepted $\operatorname{erf}(x)$ is an odd function, therefore, $$ \begin{align} \int_{-\infty}^\infty(\operatorname{erf}(a+x)+\operatorname{erf}(a-x))\;\mathrm{d}x Mathematica: erf is implemented as Erf and Erfc in Mathematica for real and complex arguments, which are also available in Wolfram Alpha. Generated Mon, 17 Oct 2016 03:52:32 GMT by s_wx1131 (squid/3.5.20)

J. (March 1993), "Algorithm 715: SPECFUN—A portable FORTRAN package of special function routines and test drivers" (PDF), ACM Trans. The error function at +∞ is exactly 1 (see Gaussian integral). Princeton, NJ: Princeton University Press, p.105, 2003. ISBN0-486-61272-4.

Google search: Google's search also acts as a calculator and will evaluate "erf(...)" and "erfc(...)" for real arguments. Level of Im(ƒ)=0 is shown with a thick green line. M.; Petersen, Vigdis B.; Verdonk, Brigitte; Waadeland, Haakon; Jones, William B. (2008). Supancic, "On Bürmann's Theorem and Its Application to Problems of Linear and Nonlinear Heat Transfer and Diffusion," The Mathematica Journal, 2014.

Flow Chart with tikzpicture: particular tipes of arrows Appease Your Google Overlords: Draw the "G" Logo De kio “saluton” estas la rekta objekto? Another form of erfc ( x ) {\displaystyle \operatorname 2 (x)} for non-negative x {\displaystyle x} is known as Craig's formula:[5] erfc ( x | x ≥ 0 Subtract $4a$ from $(3)$ using $(1)$ and $(2)$ to get $$ \int_{-\infty}^\infty\left(\operatorname{erf}(a+x)\operatorname{erf}(a-x)+1 \right)\;\mathrm{d}x =4a\operatorname{erf}(\sqrt{2}a)+\frac{2\sqrt{2}}{\sqrt{\pi}}\;e^{-2a^2}\tag{4} $$ My guess is you want either $(3)$ or $(4)$. Level of Im(ƒ)=0 is shown with a thick green line.

This directly results from the fact that the integrand e − t 2 {\displaystyle e^{-t^ − 2}} is an even function. All generalised error functions for n>0 look similar on the positive x side of the graph. After division by n!, all the En for odd n look similar (but not identical) to each other. D: A D package[16] exists providing efficient and accurate implementations of complex error functions, along with Dawson, Faddeeva, and Voigt functions.

Generated Mon, 17 Oct 2016 03:52:32 GMT by s_wx1131 (squid/3.5.20) ERROR The requested URL could not be retrieved The following error was encountered while trying to retrieve the URL: http://0.0.0.10/ Connection ISBN978-1-4020-6948-2. ^ Winitzki, Sergei (6 February 2008). "A handy approximation for the error function and its inverse" (PDF). How to draw a path with coordinates defined by f(x) Can I release a pattern without releasing the whole held expression? J.; Lozier, Daniel M.; Boisvert, Ronald F.; Clark, Charles W., NIST Handbook of Mathematical Functions, Cambridge University Press, ISBN978-0521192255, MR2723248 External links[edit] MathWorld – Erf Authority control NDL: 00562553 Retrieved from

Schöpf and P. Privacy policy About Wikipedia Disclaimers Contact Wikipedia Developers Cookie statement Mobile view Algebra Applied Mathematics Calculus and Analysis Discrete Mathematics Foundations of Mathematics Geometry History and Terminology Number Theory Probability and R. (March 1, 2007), "On the calculation of the Voigt line profile: a single proper integral with a damped sine integrand", Monthly Notices of the Royal Astronomical Society, 375 (3): 1043–1048,