Re: Integration Problem
- To: mathgroup at smc.vnet.net
- Subject: [mg126369] Re: Integration Problem
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Fri, 4 May 2012 06:25:55 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
On 5/3/12 at 4:34 AM, michael.musheghian at gmail.com (Michael
Musheghian) wrote:
>I found that evaluation of this 2 integrals yield a bit different
>result. What could be the reason?
>Integrate[E^(-1/10 ((1 + r2z)^2)), {r2z, -Infinity, Infinity}]
>Integrate[E^(-0.1 ((1 + r2z)^2)), {r2z, -Infinity, Infinity}]
The first gives an exact result, the second a numerical approximation. The
small complex component of
In[2]:= Integrate[E^(-0.1 ((1 + r2z)^2)), {r2z, -Infinity, Infinity}]
Out[2]= 5.60499 -2.03152*10^-16 I
is the result of small errors introduced by imprecise values. Do
In[3]:= Chop@
Integrate[E^(-0.1 ((1 + r2z)^2)), {r2z, -Infinity, Infinity}]
Out[3]= 5.60499
to get rid of it.