MathGroup Archive 2004

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Hypergeometric function

  • To: mathgroup at
  • Subject: [mg50209] Re: Hypergeometric function
  • From: Paul Abbott <paul at>
  • Date: Fri, 20 Aug 2004 04:58:06 -0400 (EDT)
  • Organization: The University of Western Australia
  • References: <cg20ms$p0q$>
  • Sender: owner-wri-mathgroup at

In article <cg20ms$p0q$1 at>, jujio77 at (Scott) 

> I have a finite alternating series of hypergeometric (2F1) functions.

Why not give the series?

> These functions have complex parameters.  When I sum the series I get
> larger and larger values.  

THen perhaps it is divergent?

> My question is this,  does anyone know how
> precise Mathematica is when calculating a hypergeometric fn
> numerically ie, how many sig figs are correct?

Are you working with machine precision or arbitrary precision? For 
example, compare

  machine = Hypergeometric2F1[1 + 2 I, 2 - I, 3 - I, 0.95]


  arbitrary = Hypergeometric2F1[1 + 2 I, 2 - I, 3 - I, 0.95`30]

In the second case the argument is given with Precision 30. If you 
compute the difference between these expressions

  machine - arbitrary

you will see that the machine precision result is correct to 

> I have done various transformations on the hypergeometric fn and then
> summed the series.  Each time I arrive at the same result.

Which is good to hear, at least from a consistency viewpoint.


Paul Abbott                                   Phone: +61 8 9380 2734
School of Physics, M013                         Fax: +61 8 9380 1014
The University of Western Australia      (CRICOS Provider No 00126G)         
35 Stirling Highway
Crawley WA 6009                      mailto:paul at 

  • Prev by Date: Re: Re: Beware of NSolve
  • Next by Date: Re: Plotting a contour plot with cylindrical co-ordinates
  • Previous by thread: Re: Hypergeometric function
  • Next by thread: GUIKit FileDialog Widget