MathGroup Archive 2007

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

Search the Archive

Integrate bug

  • To: mathgroup at smc.vnet.net
  • Subject: [mg76689] Integrate bug
  • From: dimitris <dimmechan at yahoo.com>
  • Date: Sat, 26 May 2007 04:20:27 -0400 (EDT)

$VersionNumber
5.2

In[75]:=
int1 = (1/(2*Pi*I))*Integrate[1/o, {o, 1, I, -1, -I, 1}]
Out[75]=
1

In[76]:=
int2 = (1/(2*Pi*I))*Integrate[1/o, {o, r, r*I, -r, (-r)*I, r},
Assumptions -> r > 0]
Out[76]=
1

In[78]:=
int3 = (1/(2*Pi*I))*Integrate[Exp[2/o], {o, 1, I, -1, -I, 1}]
Out[78]=
2

In[82]:=
int4 = (1/(2*Pi*I))*Integrate[Exp[2/o], {o, r, r*I, -r, (-r)*I, r},
Assumptions -> r > 0]
Simplify[int4]

Out[82]=
-((I*((-E^(-2/r))*r - E^(2/r)*r + (E^(-2/r) - I*E^((2*I)/r))*r +
(I*E^((2*I)/r) + E^(2/r))*r))/(2*Pi))
Out[83]=
0

inti (i=1,2,3) are correct (residue theorem)
int4 is incorrect (it should be 2; residue theorem)

1)Any ideas for workarounds in version 5.2?
2)What does version 6 do?

Thanks
Dimitris



  • Prev by Date: Re: How to subtract two sets of data for a ListPlot
  • Next by Date: Integrate bugs
  • Previous by thread: Re: messages
  • Next by thread: Re: Integrate bug