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Subject: Re: Newton method to inverse a function
Date: Sun, 22 May 2011 18:07:05 +0000 (UTC)
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"Oana" wrote in message <iramfs$6mg$1@newscl01ah.mathworks.com>...
> I need a solution for inversing the special error function, erf(x), using the Newton method.
> Is there any way to solve the equation erf(x)=y using this method?
- - - - - - - - 
  A single hint: In the Newton-Raphson method you will need the derivative of erf(x) with respect to x.  It will be just its density function evaluated at the upper limit of integration, 2/sqrt(pi)*exp(-x^2).

Roger Stafford