[R] How to do it without for loops?

[Uwe Ligges]

On Tue, 28 Feb 2006, ronggui wrote:

> This is the code:
> 
> x<-matrix(rnorm(20),5)
> y<-list()
> for (i in seq(nrow(x))) y[[i]]<-t(x[i,,drop=F])%*%x[i,,drop=F]
> y[[1]]+y[[2]]+y[[3]]+y[[4]]+y[[5]]
> 
> How can I do it without using for loops?

 crossprod(x)

Uwe Ligges

> Thank you in advance!
> --
> ronggui
> Deparment of Sociology
> Fudan University
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
>