[R] Matrix operations

[Bill.Venables at csiro.au]

Oops.  Try

A <- sum(X * solve(V, X))

(too fast!) 

-----Original Message-----
From: Venables, Bill (CMIS, Cleveland) 
Sent: Tuesday, 29 June 2010 1:05 PM
To: 'Dmitrij Kudriavcev'; 'r-help at r-project.org'
Subject: RE: [R] Matrix operations

Since X is a vector, then

A <- sum(X, solve(V, X)) 

is probably slightly better here.

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Dmitrij Kudriavcev
Sent: Tuesday, 29 June 2010 12:29 PM
To: r-help at r-project.org
Subject: [R] Matrix operations

Hello

I have a quick question.

I need to compute matrix in R, like A <- t(X) %*% solve(V) %*% X, where X is
a vector and V is a matrix

This code works, but now i want to optimize it. I have try:

A <- crossprod(X, solve(V)) %*% X

Is there another, better way?

WBR
Dima

	[[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
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.