On Mon, Sep 8, 2008 at 19:22, Devon McCormick <[EMAIL PROTECTED]> wrote:
> We haven't ended quite yet. Perhaps you remember the article by Ewart Shaw
> in Vector 18.4, in which he defined the error function erf using J's
> hypergeometric conjunction:
>
> erf =: (*&(%:4p_1)%^@:*:)*[:1 H. 1.5*:    NB. A&S 7.1.21 (right)
>
> and then defined the cumulative distribution function of the normal
> distribution by:
>
> cnd =: [:-:1:+[:erf%&(%:2)            NB. A&S 26.2.29 (solved for P)
> )

I don't know know what the original source is, but it's such a nice
phrase that a variant of it even in the Dictionary entry for the H.
primitive.

Ambrus
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