R help - Jan 2006 - [Q] extracting lower diagonal elements of a matrix

Hi R users

I like to extract lower diagonal elements of a matrix in such a way like, 
data[1,2], data[1,3],
...., data[5,6] are extracted from a matrix called 'data'

This short script below is what I have written so far.

##########################################
data <- matrix(rnorm(36,0,1),nrow=6)
temp<-c()
for (i in 1:(nrow(data)-1))
{
    for (j in (i+1):nrow(data))
    {
        temp<-append(temp,data[j,i])
    }
}
##########################################

Is there any function for this?  or is there any elegant way to do this 
task?

Thanks in advance.

TM

try:
as.vector(as.dist(data))


Taka Matzmoto a ??crit :
>Hi R users
>
>I like to extract lower diagonal elements of a matrix in such a way like, 
>data[1,2], data[1,3],
>...., data[5,6] are extracted from a matrix called 'data'
>
>This short script below is what I have written so far.
>
>##########################################
>data <- matrix(rnorm(36,0,1),nrow=6)
>temp<-c()
>for (i in 1:(nrow(data)-1))
>{
>    for (j in (i+1):nrow(data))
>    {
>        temp<-append(temp,data[j,i])
>    }
>}
>##########################################
>
>Is there any function for this?  or is there any elegant way to do this 
>task?
>
>Thanks in advance.
>
>TM
>
>______________________________________________
>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
>
>  
>

Try

s <- matrix(rnorm(36,0,1),nrow=6)
s[col(s)<row(s)]

Courtesy of V&R.

-Christos 

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Taka Matzmoto
Sent: Friday, January 27, 2006 1:13 AM
To: r-help at stat.math.ethz.ch
Subject: [R] [Q] extracting lower diagonal elements of a matrix

Hi R users

I like to extract lower diagonal elements of a matrix in such a way like,
data[1,2], data[1,3], ...., data[5,6] are extracted from a matrix called
'data'

This short script below is what I have written so far.

##########################################
data <- matrix(rnorm(36,0,1),nrow=6)
temp<-c()
for (i in 1:(nrow(data)-1))
{
    for (j in (i+1):nrow(data))
    {
        temp<-append(temp,data[j,i])
    }
}
##########################################

Is there any function for this?  or is there any elegant way to do this
task?

Thanks in advance.

TM

______________________________________________
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

?lower.tri
hih