Re: Assumptions in fancy-notation integrals
- To: mathgroup at smc.vnet.net
 - Subject: [mg44360] Re: Assumptions in fancy-notation integrals
 - From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
 - Date: Fri, 7 Nov 2003 05:16:04 -0500 (EST)
 - Organization: Universitaet Leipzig
 - References: <bob700$qo9$1@smc.vnet.net>
 - Reply-to: kuska at informatik.uni-leipzig.de
 - Sender: owner-wri-mathgroup at wolfram.com
 
Hi,
enclose the integral  with Assuming[] ??
Regards
  Jens
  
Curt Fischer wrote:
> 
> Dear Group,
> 
> I know I can do Integrate[stuff[x],{x,0,y},Assumptions->otherstuff] to
> specify, for instance, that a certain parameter in my system is a positive
> real.
> 
> Can I incorporate Assumptions into an Integral entered with the escape code
> [esc]dintt[esc]?  For example:
> 
> In[32]:=
> stuff[x_]:=2 x
> 
> In[33]:=
> Integrate[k stuff[x],{x,0,1},Assumptions\[Rule]Re[k]>0]
> Out[33]=
> k
> 
> The above evaluates fine, although for this toy example there is no meaning
> or benefit from making the Assumptions.  But below things don't work.  Is
> there a fix?
> 
> In[33]:=
> \!\(\((\[Integral]\_0\%1 k\ stuff[x] \[DifferentialD]x)\),
>   Assumptions \[Rule] Re[k] > 0\)
> \!\(\*
>   RowBox[{\(Syntax::"tsntxi"\), \(\(:\)\(\ \)\), "\<\"\\\"\\!\\(\\(\\((\\(\
> \[Integral]\\_0\\%1\\) \\(\\(k\\(\\(stuff[x]\\)\\) \\(\\(\[DifferentialD] \
> x\\)\\)\\)\\))\\)\\), \\(\\(Assumptions \[Rule] \\(\\(\\(\\(Re[k]\\)\\) > \
> 0\\)\\)\\)\\)\\)\\\" is incomplete; more input is needed.\\!\\(\\\"\\\"\\) \
> \\!\\(\\*ButtonBox[\\\"More\[Ellipsis]\\\",
> ButtonStyle->\\\"RefGuideLinkText\
> \\\", ButtonFrame->None, ButtonData:>\\\"General::tsntxi\\\"]\\)\"\>"}]\)
> \!\(\*
>   StyleBox[
>     ErrorBox[\(\((\[Integral]\_0\%1 k  stuff[x] \[DifferentialD]x)\),
>       Assumptions \[Rule] Re[k] > 0\)],
>     ShowStringCharacters->True]\)
> 
> --
> Curt Fischer