From: francogrex <francogrex_at_mail.com>

Date: Fri, 18 Apr 2008 15:11:20 -0700 (PDT)

Date: Fri, 18 Apr 2008 15:11:20 -0700 (PDT)

There are a lot of syntax errors such as unclosed parentheses, missing commas etc; Example: exp@(@lgamma((k+1)/2)-lgamma(k/2)*1/sqrt(k), where the parenthesis between the @s is not closed. I suggest you get an editor such as "Tinn" that can highlight those for you. In addition I notice that you use two functions: f and g, in a loop but you didn't pass any arguments to them.

jinjin wrote:

*>
*

> I am trying to solve the integration equation, for different values of K

*> from 4 to 25, the integration is with respect to u,
**> Here is the equation: gamma(k/2) / ( sqrt(k-1)*gamma((k-1)/2) ) *
**> integrate(f= (1+u^2/k-1)^(-k/2), lower=0, upper= sqrt(a^2*k/(k+1-a^2)) ) =
**> the similar expression as te left hand except k becomes k+1
**> my code is below, I don't know why R keep telling me the syntax wrong but
**> I am not clear, thanks.
**> f<-function(u,k){(1+u^2/(k-1))^(-k/2)}
**> g<-function(u,k){(1+u^2/k)^(-(k+1)/2)}
**> for(k in 4:25){
**> out<-uniroot(function(a){
**> m<-exp(lgamma(k/2)-lgamma((k-1)/2))*1/sqrt(k-1)
**> n<-exp(lgamma((k+1)/2)-lgamma(k/2)*1/sqrt(k)
**> m*integrate(f,lower=0,upper=sqrt(a^2*(k-1)/(k-a^2)),rel.tol=.Machine$double.eps^0.25)
**> -n*integrate(g,lower=0,upper=sqrt(a^2*k/(k+1-a^2)),rel.tol=.Machine$double.eps^0.25)
**> }
**> lower=1.4, upper=2)
**> print(unlist(out))}
**>
*

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