MathGroup Archive 2004

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

Search the Archive

Re: Trouble : simple stuffs for beginner

  • To: mathgroup at smc.vnet.net
  • Subject: [mg48280] Re: Trouble : simple stuffs for beginner
  • From: Julien MARY <julien.mary at free.fr>
  • Date: Fri, 21 May 2004 03:54:29 -0400 (EDT)
  • References: <c8f236$d3l$1@smc.vnet.net> <c8hp31$fun$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

	The boolean relation will be 0 if false 1 if true. Then it mean a 
caracteristic fonction (like in measure theory) which is equal to 1 if 
x is between 2k-1 and 2k+1 and 0 elsewhere.

Jens-Peer Kuska wrote:
> Hi,
> 
> what mean 
> 
> (-1)^k(2k - t)(2k - 1 < x <= 2k + 1)E[-(t - x)^2/2]
> 
> ?? Multiply by a boolenan relation ??
> 
> I will not understand this and it has nothing to do with
> Mathematica syntax .. can you explain what this is ??
> 
> Regards
>   Jens
> 
> Julien MARY wrote:
> 
>>        Hello,
>>
>>   I am using Mathematica 4.0 with Linux Debian.
>>
>>   I am defining :
>>
>>        g[x_] := Sum[
>>     Integrate[(-1)^k(2k - t)(2k - 1 < x <= 2k + 1)E[-(t - x)^2/2],
>>       t], {k, -Infinity, Infinity}]
>>
>>To be clear, it the convolution of  arcsin(sin(x))/2Pi with exp(-x²/2)
>>
>>        The I want to plot g[x] with Plot[g[x],{x,-10,10}] and Mathematica is
>>insulting me. Bug of Mathematica of Bug of my using of it ?
>>
>>                Julien
>>========================================================================
>>        \!\(NSum::"nsnum" \(\(:\)\(\ \)\)
>>     "Summand (or its derivative) \!\(\[Integral] \(\(\[LeftSkeleton] 1 \
>>\[RightSkeleton]\)\)\) is not numerical at point \!\(k\) = \!\(46661\)."\)d1
>>
>>General::"stop": "Further output of \!\(NSum :: \"nsnum\"\) will be \
>>suppressed during this calculation."
>>
>>Plot::"plnr": "\!\(g[x]\) is not a machine-size real number at \!\(x\) = \
>>\!\(-9.999999166666667`\)."tpp
>>
>>....... etc ...
>>==========================================================================
> 
> 


  • Prev by Date: padding numbers in front of uniquely generatd names
  • Next by Date: SetPrecision - What does in find?
  • Previous by thread: Re: Trouble : simple stuffs for beginner
  • Next by thread: Re: Trouble : simple stuffs for beginner