Version differences in Integrate with Min[] in the integrand
- To: mathgroup at smc.vnet.net
- Subject: [mg55858] Version differences in Integrate with Min[] in the integrand
- From: Gareth Russell <gjr2008 at columbia.edu>
- Date: Fri, 8 Apr 2005 01:36:30 -0400 (EDT)
- Organization: Columbia University
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
I don't think this is a function of differences in the internal use of
Simplify. Anyone have an idea about what is going on here?
Gareth Russell
Columbia University
Integrate[Exp[-r*(Min[d2,t1]-Min[
d1,t1])]/((d12-d11)*(d22-d21)),{d1,d11,d12},{d2,d21,d22}]
The result in v4.2
\!\(\(â?«\_d11\%d12\(â?«\_d21\%d22\( \[ExponentialE]\^\(\(-r\)\ \((\(-Min[d1, t1]\
\) + Min[d2, t1])\)\)\) \[DifferentialD]d2 \
\[DifferentialD]d1\)\)\/\(\((\(-d11\) + d12)\)\ \((\(-d21\) + d22)\)\)\)
The result in v5.0
\!\(\(\[ExponentialE]\^\(\(-d21\)\ r\)\ \((\(-\[ExponentialE]\^\(d11\ r\)\) - \
\[ExponentialE]\^\(d21\ r\) + \[ExponentialE]\^\(r\ \((d11 + d21 - t1)\)\) + \
\[ExponentialE]\^\(r\ t1\))\)\)\/\(\((d11 - d12)\)\ \((d21 - d22)\)\ r\^2\)\)
(Incorrect, I think...)
The result in v5.1.0
Nothing: runs for many minutes.