Problem with Integrate
- To: mathgroup at smc.vnet.net
- Subject: [mg9423] Problem with Integrate
- From: Pedro A Santos <pasantos at math.ist.utl.pt>
- Date: Wed, 5 Nov 1997 01:56:39 -0500
- Organization: I.S.T. - Portugal
- Sender: owner-wri-mathgroup at wolfram.com
Hello,
I hope somebody can help me with a problem:
When I try to use Integrate as
In[1]= Integrate[Exp[-I*w*x]*(1-Exp[I*w])/w,{w,-Infinity, Infinity}]
I get the answer
\!\(\*
RowBox[{
\(Integrate::"idiv"\), \( : \ \),
"\<"Integral of \!\(\(E\^\(\(-I\)\\ w\\ x\)\\ \((1 - E\^\(I\\
w\))\)\)\/w\
\) does not converge on \!\({\*InterpretationBox[\(-\\[Infinity]\), \
DirectedInfinity[-1]], \*InterpretationBox[\"\\[Infinity]\", \
DirectedInfinity[1]]}\)."\>"}]\)
Even if I put the option PrincipalValue -> True. But if I write
In[2]= InverseFourierTransform[(1-Exp[I*w])/w,w,x]
I get the correct answer
Out[2]= \!\(\(-I\)\ UnitStep[1 - x, ZeroValue \[Rule] 1\/2] +
I\ UnitStep[\(-x\), ZeroValue \[Rule] 1\/2]\).
Does somebody know why this happens? Thanks
Pedro Santos