Re: Bug with Integrate in v7?
- To: mathgroup at smc.vnet.net
- Subject: [mg103136] Re: Bug with Integrate in v7?
- From: dh <dh at metrohm.com>
- Date: Wed, 9 Sep 2009 04:42:00 -0400 (EDT)
- References: <h859sa$pva$1@smc.vnet.net>
Hi,
you are right: serious bug. Would send a note to Wolfram.
Daniel
kostka wrote:
> Okay it took me an hour to track this down, and the only explanation I
> can see is that there is a bug in Mathematica v7 with Integral[] with
> multiple bounds.
>
> In v7.0 (answers should both be 512/27, only one of them is):
>
> In[1]:= f = (x - 1)^2*(y - 1)^2*(z - 1)^2;
> Integrate[f, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}]
> Integrate[Integrate[Integrate[f, {x, -1, 1}], {y, -1, 1}], {z, -1, 1}]
>
> Out[2]= 0
>
> Out[3]= 512/27
>
>
> In v6.0 (correct behavior):
>
> In[1]:= f = (x - 1)^2*(y - 1)^2*(z - 1)^2;
> Integrate[f, {x, -1, 1}, {y, -1, 1}, {z, -1, 1}]
> Integrate[
> Integrate[Integrate[f, {x, -1, 1}], {y, -1, 1}], {z, -1, 1}]
>
> Out[2]= 512/27
>
> Out[3]= 512/27
>
>
> Serious bug, right? Or am I missing something obvious?
>
> Tim
>