I have a question on the function 'embed'. I ran the example

x <- 1:10
embed(x, dimension=3)

This gives the output:

     [,1] [,2] [,3]
[1,]    3    2    1
[2,]    4    3    2
[3,]    5    4    3
[4,]    6    5    4
[5,]    7    6    5
[6,]    8    7    6
[7,]    9    8    7
[8,]   10    9    8

I don't quite understand the output and why it is useful. First, there are only 
8 rows down from 10 and the first element starts with 3. Of course I can think 
of explanations as to what is occuring but I cannot see how this is useful. I 
am sure it has application as i see this command used in much of the source but 
I just cannot see it now.

The documentation states:

Each row of the resulting matrix consists of sequences x[t], x[t-1], ..., 
x[t-dimension+1], where t is the original index of x. If x is a matrix, i.e., x 
contains more than one variable, then x[t] consists of the tth observation on 
each variable. 

This explanation doesn't seem to account for the dimension argument.

Thank you for your comments.

Kevin

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