Re: Bivariate Integrations/Assumptions error
- To: mathgroup@smc.vnet.net
- Subject: [mg10704] Re: Bivariate Integrations/Assumptions error
- From: Paul Abbott <paul@physics.uwa.edu.au>
- Date: Fri, 30 Jan 1998 04:24:39 -0500
- Organization: University of Western Australia
- References: <6ahmj1$pf3@smc.vnet.net>
Mary Lesperance wrote:
> Mathematica has trouble with bivariate integrations. I tried the
> following: (The answer is 1 for any real Phi and Psi - this is just
> the product of 2 normal densities)
>
> f[x_,y_,\[Phi]_,\[Psi]_,n_]:=.5*Exp[-.5*((x-\[Phi])^2 + (y-(\[Phi]^2
> + \[Psi]))^2)]/Pi
Replacing the inexact 0.5 by the exact 1/2 works better:
In[1]:=SetOptions[Integrate, GenerateConditions -> False];
In[2]:= Integrate[Exp[-(1/2)*((x - \[Phi])^2 +
(y - (\[Phi]^2 + \[Psi]))^2)]/(2*Pi),
{x, -Infinity, Infinity}, {y, -Infinity, Infinity}]
Out[2]= 1
Cheers,
Paul
____________________________________________________________________
Paul Abbott Phone: +61-8-9380-2734
Department of Physics Fax: +61-8-9380-1014
The University of Western Australia Nedlands WA 6907
mailto:paul@physics.uwa.edu.au AUSTRALIA
http://www.pd.uwa.edu.au/~paul
God IS a weakly left-handed dice player
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