Category Education License Standard YouTube License Show more Show less Loading... share|cite|improve this answer answered May 8 '11 at 22:41 Qiaochu Yuan 229k29455778 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. Arfken, G.

Applied Mathematics Series. 55 (Ninth reprint with additional corrections of tenth original printing with corrections (December 1972); first ed.). Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the 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. M.

DrJamesTanton 13,324 views 13:45 Diffusion - Coefficients and Non Steady State - Duration: 23:29. Handbook of Continued Fractions for Special Functions. In order of increasing accuracy, they are: erf ( x ) ≈ 1 − 1 ( 1 + a 1 x + a 2 x 2 + a 3 x The integrand ƒ=exp(−z2) and ƒ=erf(z) are shown in the complex z-plane in figures 2 and 3.

Supancic, "On Bürmann's Theorem and Its Application to Problems of Linear and Nonlinear Heat Transfer and Diffusion," The Mathematica Journal, 2014. share|cite|improve this answer answered May 9 '11 at 4:18 J. As it is necessary that the function should have a name, and as I do not know that any has been suggested, I propose to call it the Error-function, on account Washington D.C., USA; New York, USA: United States Department of Commerce, National Bureau of Standards; Dover Publications.

Continued Fractions. Please try the request again. New York: Chelsea, 1999. Similarly, the En for even n look similar (but not identical) to each other after a simple division by n!.

Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. History and Terminology>Wolfram Language Commands> MathWorld Contributors>D'Orsogna> Less... Haskell: An erf package[18] exists that provides a typeclass for the error function and implementations for the native (real) floating point types. Indeed, Φ ( x ) = 1 2 π ∫ − ∞ x e − t 2 2 d t = 1 2 [ 1 + erf ( x 2

is the double factorial: the product of all odd numbers up to (2n–1). doi:10.1090/S0025-5718-1969-0247736-4. ^ Error Function and Fresnel Integrals, SciPy v0.13.0 Reference Guide. ^ R Development Core Team (25 February 2011), R: The Normal Distribution Further reading[edit] Abramowitz, Milton; Stegun, Irene Ann, eds. Referenced on Wolfram|Alpha: Erf CITE THIS AS: Weisstein, Eric W. "Erf." From MathWorld--A Wolfram Web Resource. current community blog chat Mathematics Mathematics Meta your communities Sign up or log in to customize your list.

For complex double arguments, the function names cerf and cerfc are "reserved for future use"; the missing implementation is provided by the open-source project libcerf, which is based on the Faddeeva Up next Error Function and Complimentary Error Function - Duration: 5:01. C++: C++11 provides erf() and erfc() in the header cmath. All generalised error functions for n>0 look similar on the positive x side of the graph.

Mathematica: erf is implemented as Erf and Erfc in Mathematica for real and complex arguments, which are also available in Wolfram Alpha. Another approximation is given by erf ( x ) ≈ sgn ( x ) 1 − exp ( − x 2 4 π + a x 2 1 New York: Dover, pp.297-309, 1972. Fortran 77 implementations are available in SLATEC.

Also has erfi for calculating i erf ( i x ) {\displaystyle i\operatorname {erf} (ix)} Maple: Maple implements both erf and erfc for real and complex arguments. Conf., vol. 2, pp. 571–575. ^ Van Zeghbroeck, Bart; Principles of Semiconductor Devices, University of Colorado, 2011. [1] ^ Wolfram MathWorld ^ H. What (combination of) licenses is popular for public/shared proprietary software (“Feel free to contribute, but only we can make commercial use”)? 5008 out of the box How much interest should I 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".

C++: C++11 provides erf() and erfc() in the header cmath. For complex

New York: Dover, pp.179-182, 1967. So those of us interested in its most important application are stuck with conversions... ...A search of the Internet will show many applications of what we now call $\mathrm{erf}$ or $\mathrm{erfc}$ Negative integer values of Im(ƒ) are shown with thick red lines. For previous versions or for complex arguments, SciPy includes implementations of erf, erfc, erfi, and related functions for complex arguments in scipy.special.[21] A complex-argument erf is also in the arbitrary-precision arithmetic

If L is sufficiently far from the mean, i.e. μ − L ≥ σ ln k {\displaystyle \mu -L\geq \sigma {\sqrt {\ln {k}}}} , then: Pr [ X ≤ L Given random variable X ∼ Norm [ μ , σ ] {\displaystyle X\sim \operatorname {Norm} [\mu ,\sigma ]} and constant L < μ {\displaystyle L<\mu } : Pr [ X Related 10Integral of product of two error functions (erf)4Taylor Expansion of Error Function1An integral of a complementary error function3Can $\Phi^{-1}(x)$ be written in terms of $\operatorname{erf}^{-1}(x)$?0Distribution under null-hypothesis and type 1 Using the alternate value a≈0.147 reduces the maximum error to about 0.00012.[12] This approximation can also be inverted to calculate the inverse error function: erf − 1 ( x )

Wall, H.S. Derivative and integral[edit] The derivative of the error function follows immediately from its definition: d d z erf ( z ) = 2 π e − z 2 . {\displaystyle Book of zen kōans Flow Chart with tikzpicture: particular tipes of arrows With modern technology, is it possible to permanently stay in sunlight, without going into space? The denominator terms are sequence A007680 in the OEIS.

Conference presenting: stick to paper material? Excel: Microsoft Excel provides the erf, and the erfc functions, nonetheless both inverse functions are not in the current library.[17] Fortran: The Fortran 2008 standard provides the ERF, ERFC and ERFC_SCALED Ramanujan: Twelve Lectures on Subjects Suggested by His Life and Work, 3rd ed.