[R] error: contextstack overflow

[Mahmoud via R-help]

Dear r users
I've a loop that has 20 if else statements but it gave me the ""contextstack 
overflow"" error at statement 14 
Is there any way to overcome this problem cause i'm forced to do that loop 
any help or recommendations please

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

[R] write a function inside the summation in a more condensed form

[Mahmoud via R-help]

Dear R Experts
that's my original equation

> x=c(2,4)

> Y1=sum(sapply(1:2,function(i){sum(sapply(1:i,function(j){(3^(x[i]+x[j]))}))}))
>  
> y1 
[1] 7371 
 I want to write the inside function (3^(x[i]+x[j])) in a more condensed form 
cause this will help me when the multiple summations are more than two 

I've tried the following form

> y2=sum(sapply(1:2,function(i){sum(sapply(1:i,function(j){(3^(sum(sapply(i:j,function(l){x[l]}}))}))
>  
> y2 
[1] 819 


But it didn't work, it gave another solution 
Any help or recommendations

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

[R] summation involving multiple summations

[Mahmoud via R-help]

Dear R Experts 

I've a function which involves multiple summations, and the number of 
summations depends on a 
random variable named (n-r), where n is known but r is random and rn_r=3 
>fx=function(x)sum(sapply(1:n_r, function(j1) {sum(sapply(1:(j1), 
>function(j2){sum(sapply(1:(j2), 
>function(j3){(j1>j2)*(j2>j3)/(x+exp(tc[j1]+tc[j2]+tc[j3])^4}))}))}))} 

The value of r will be generated from a simulation process, so in one iteration 
r may be equal to 0, and in another iteration it might be equal to 2 and so on, 
and accordingly  (n-r) is either 1, 2, or 3. And this makes the body of the 
summation different every time. 


Here's my  trail code in the simple case when n=3: 

library(nleqslv) 
N=100;n=3 
a=matrix(0,nrow=N,ncol=1) 
for(i in 1:N){ 
tc=matrix(0, nrow=n, ncol=1) 
t=matrix(0, nrow=n, ncol=1) 
c=matrix(0,nrow=n,ncol=1) 
for(j in 1: n){ 
t[j]=rexp(1,rate=3) 

c[j]=rexp(1, rate =2) 
if (t[j]>=c[j]) {tc[j]=t[j]} 
} 
n_r=nrow(tc) 
if(n_r==1){fx=function(x)sum(sapply(1:n-3, function(j1){1/(x+exp(tc[j1]))^4})) 
a[i]=nleqslv(0.5, fx)$x 
} 
if(n_r==2){fx=function(x)sum(sapply(1:n-2, 
function(j1){sum(sapply(1:(j1),function(j2){(j1>j2)/(x+exp(tc[j1]+tc[j2]))^4}))}))
 
a[i]=nleqslv(0.5, fx)$x 
} 
if(n_r==3){fx=function(x)sum(sapply(1:n, function(j1) {sum(sapply(1:(j1), 
function(j2){sum(sapply(1:(j2), 
function(j3){(j1>j2)*(j2>j3)/(x+exp(tc[j1]+tc[j2]+tc[j3]))^4}))}))})) 
a[i]=nleqslv(0.5, fx)$x 
} 
} 

Is there any other way to write a loop that could be executed for any value of 
r instead of putting the if ()  statement for each single value of r , as n may 
take large values reaching 30, for instance. 

Any help or recommendation for a reference that can help me would be 
appreciated . 
Thank you
Mahmoud Farid

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.