Re: Series on HypergeometricPFQ
- To: mathgroup at smc.vnet.net
- Subject: [mg126364] Re: Series on HypergeometricPFQ
- From: David Bailey <dave at removedbailey.co.uk>
- Date: Thu, 3 May 2012 22:24:51 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jntg96$29$1@smc.vnet.net>
On 03/05/2012 09:40, Yi Wang wrote:
> Hi, all
>
> I encountered errors when doing the following expansion:
>
> Series[HypergeometricPFQ[{a, a}, {b, c, d}, x], {x, \[Infinity], 0}]
>
> The error message is:
>
> Table::iterb: "Iterator {K3,0,Ceiling[-Re[a]]} does not have appropriate bounds. "
>
> Any idea what's wrong in the above expansion? Many thanks!
>
> --- work around ---
>
> Alternatively, I could first add a small eps factor in the expansion, and eventually take it to zero:
>
> Series[HypergeometricPFQ[{a, a+eps}, {b, c, d}, x], {x, \[Infinity], 0}]
>
> The result looks reasonable. However it is very complicated and unnatural for a large expression.
>
>
If you want the basic series expansion from x=0, this is the correct syntax:
Series[HypergeometricPFQ[{a, a}, {b, c, d}, x], {x, 0, 4}]
(Where 4 is the number of terms to print)
David Bailey
http://www.dbaileyconsultancy.co.uk