Problem when NIntegrate matrix
- To: mathgroup at smc.vnet.net
- Subject: [mg81341] Problem when NIntegrate matrix
- From: chiron1201 <huangj at cse.buaa.edu.cn>
- Date: Wed, 19 Sep 2007 05:41:39 -0400 (EDT)
Hi all!
I can not understand why there is a NIntegrate::inum error when I try to evaluate the following code
TEST = Piecewise[{
{{{1, 2, 3}, {2, 3, 4}, {3, 4, 5}}, #1 < 0.00},
{{{2, 3, 4}, {3, 4, 5}, {4, 5, 6}}, #1 >= 0.00},
}] &;
NIntegrate[TEST[x], {x, -1, +1}]
However, I can get the correct result by modifying the code manually. That is
NIntegrate[{{1, 2, 3}, {2, 3, 4}, {3, 4, 5}}, {x, -1, 0}]+NIntegrate[{{2, 3,4}, {3, 4, 5}, {4, 5, 6}}, {x, 0, 1}]
However, it is impossible for me to manually split the integration range to thousands of segments. Why this happens? What should I do if I want the first code be evaluated correctly?
Thanks!