# What is error function ?

Saint
In heat transfer, some formulae are expressed in error function. what is it ?

How do we get the equation for error function ?[?]

Isn't the error function e -x 2 ? Thats all I know....

Last edited:
Guybrush Threepwood

KLscilevothma
Originally posted by On Radioactive Waves
Isn't the error function e -x 2 ? Thats all I know....
I've heard it's called imaginary error function in full.

Staff Emeritus
Gold Member
Almost... erf(x) is:

erf(x) = (2 / sqrt(&pi;)) &int;0..x e-x2 dx

It's immediate use is that it's the integral of a gaussian distribution, so it's directly applicable to statistical problems.

More generally, I understand that a lot of nonelementary functions can be expressed in terms of combinations of elementary functions and error functions, so erf expands the expressive power of closed forms.

plus
It comes up when solving some differential equations, and it is thus good to have tabulated.