Bug with Integrate in v7?
- To: mathgroup at smc.vnet.net
- Subject: [mg103116] Bug with Integrate in v7?
- From: kostka <kostka at gmail.com>
- Date: Tue, 8 Sep 2009 05:59:43 -0400 (EDT)
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