Displaying 1 result from an estimated 1 matches for "tp24612796p24614641".
2009 Jul 22
6
A question on operation on list
Hi,
I have created a list object like that :
x = vector("list")
for (i in 1:5) x[[i]] = rnorm(2)
x
Now I want to do two things :
1. for each i, I want to do following matrix calculation : t(x[[i]]) %*%
x[[i]] i.e. for each i, I want to get a 2x2 matrix
2. Next I want to get x[[1]] + x[[2]] +....
I did following : res=vector("list"); res = sapply(x, function(i) t(x[[i]])
%*%