Re: [Jprogramming] hypergeometric function in J

On 5/11/13, Roger Hui wrote: > How can anyone not have Abramowitz and Stegun ? :-) > > Anyway, the entire book is on-line, and Section 15 starts at > http://people.math.sfu.ca/~cbm/aands/page_555.htm Another digital copy is at "http://convertit.com/Go/ConvertIt/Reference/AMS55.ASP?Res=150&Page=55

Re: [Jprogramming] hypergeometric function in J

There are some hidden tricks I did not realize: for erf   =: (1 H. 1.5)@*: * 2p_0.5&* % ^@:*: and erf2 =: ] * 2p_0.5 * [: 0.5 H.1.5 [: - *: erf i.10 0 0.842701 0.995322 0.78 1 1 1 1 1 1 erf2 i.10 0 0.842701 0.995322 0.78 1 1 0.998693 _814.656 _3.47366e9 1.69158e17 erf2 blows up for big

Re: [Jprogramming] hypergeometric function in J

Henry and Roger, Thanks very much your kindly help. Just learned that there is relation between m H. n and (n-m) H. n. The erf function erf   =: (1 H. 1.5)@*: * 2p_0.5&* % ^@:*: may be rewritten to   erf2 =: ] * 2p_0.5 * [: 0.5 H.1.5 [: - *:, which is the one on  http://en.wikipedia.org/wiki/Conf

Re: [Jprogramming] hypergeometric function in J

How can anyone not have Abramowitz and Stegun ? :-) Anyway, the entire book is on-line, and Section 15 starts at http://people.math.sfu.ca/~cbm/aands/page_555.htm Examples of using H. : - http://www.jsoftware.com/jwiki/Essays/Normal_CDF

Re: [Jprogramming] hypergeometric function in J

JforC gives the formula in chapter 31. Henry Rich On 5/11/2013 11:37 AM, elton wang wrote: In J, what is the exact formula for m H.n? In dictionary, it is said to be defined in Section 15 of Abramowitz and Stegun [13], but I dont have the book. for instance, what is the (1 H. 1.5) in the erf

[Jprogramming] hypergeometric function in J

In J, what is the exact formula for m H.n? In dictionary, it is said to be defined in Section 15 of Abramowitz and Stegun [13], but I dont have the book. for instance, what is the (1 H. 1.5) in the erf function? in wiki, , how to relate the 1F1(0.5,1.5,x) to (1 H. 1.5)? thanks, -