On Oct 14, 2015, at 1:29 PM, Sherouk Moawad via R-help wrote:
> Σi=02 Σj=01(exp(xi+xj)), i>j if (i>0 and j>0) I want to write this
> summation which has a condition on numerator(j0 and j>0I tried on this
> code
That comes across as only barely comprehensible.
> sum(sapply(0:2, function(i){
Σi=02 Σj=01(exp(xi+xj)), i>j if (i>0 and j>0) I want to write this summation
which has a condition on numerator(j0 and j>0I tried on this code
sum(sapply(0:2, function(i){sum(sapply(0:1, function(j){if
(i>0&j>0){i>j}{exp(x[i]+x[j])}))}))But it didn't work Any help please
[[alternative H
On May 2, 2009, at 12:18 AM, RON70 wrote:
Can anyone please explain me why it is not coming? I have done
following :
j=1
i=0:j; sum( choose(i+j,i) )
[1] 3
j=2
i=0:j; sum( choose(i+j,i) )
[1] 10
j=3
i=0:j; sum( choose(i+j,i) )
[1] 35
j=0:3; i=0:j; sum( choose(i+j,i) )
Warning messag
Can anyone please explain me why it is not coming? I have done following :
> j=1
> i=0:j; sum( choose(i+j,i) )
[1] 3
> j=2
> i=0:j; sum( choose(i+j,i) )
[1] 10
> j=3
> i=0:j; sum( choose(i+j,i) )
[1] 35
> j=0:3; i=0:j; sum( choose(i+j,i) )
Warning message:
In 0:j : numerical expression has 4 elem
Perhaps:
SSCxy <- function(z) {tail(sapply(0:z, function (x) sum(sapply(0:x,
function(y) sum(choose(x+y, y), 1) }
> SSCxy(5)
[1] 462
See also:
http://www.research.att.com/~njas/sequences/?q=1%2C3%2C10%2C35%2C126%2C462&sort=0&fmt=0&language=english&go=Search
On May 1, 2009, at 3:45 PM
Dear R experts
I need to write a function that incorporates double summation, the problem
being that the upper limit of the second summation is the index of the first
summation, i.e:
sum_{j=0}^{x} sum_{i=0}^{j} choose(i+j, i)
where x variable or constant, doesn't matter.
The following code obviou
6 matches
Mail list logo
