Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2010

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

Search the Archive

Re: Series and passing a function a changing number of variables

  • To: mathgroup at smc.vnet.net
  • Subject: [mg106852] Re: [mg106758] Series and passing a function a changing number of variables
  • From: "David Park" <djmpark at comcast.net>
  • Date: Sun, 24 Jan 2010 05:47:41 -0500 (EST)
  • References: <7190308.1264252146443.JavaMail.root@n11>

You need to use two lists, not a single array. That is, get rid of the extra
{}.

Series[Exp[x + 2 y^x], {x, 0, 2}, {y, 0, 2}]  


David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark/  


From: Ignacio Plazeta [mailto:Ignacio.Plazeta at speednet.es] Dear Friends

-- 1 -----------------------------------------------

This command works fine:

Series[ Exp[ x + 2 y^x ] , {x, 0, 2} ,  {y, 0, 2} ]

this one doesn't:

Series[ Exp[ x + 2 y^x ] ,  {{x, 0, 2}, {y, 0, 2}} ]

It returns:

"Series specification is not a list with three elements ..."

-- 2 -----------------------------------------------

I'm trying to set up this kind of function:

myTaylorExpander[ function_ , varList , startPoint_ , ord_ ]

where varList length is changing; because of the above mentioned
behavior of Series function I can't simply try something like:

numVar = Length[ varList ];

args = Table[

{ varList[[k]] , startPoint , ord}

, { k, 1 , numVar }

]

Series[ f , args ] // Normal

-- 3 -----------------------------------------------

Is there a way to get out of this by a trick to pass a functions
a changing number of variable ? Anything else fitting is welcomed too.

Warmest Regards.

Ignacio Plazeta
( Spain )









  • Prev by Date: Re: sum done two ways gives different answers in
  • Next by Date: Re: Series and passing a function a changing number of variables
  • Previous by thread: Re: Series and passing a function a changing number of variables
  • Next by thread: Re: Series and passing a function a changing number of variables