R help - Jul 2007 - generating lower triangular matrix

Hi,
 
I would like to generate below triangular matrix for some  a.
 
0
0
0
0
0
0
1
0
0
0
0
0
a
1
0
0
0
0
a^2
a
1
0
0
0
a^3
a^2
a
1
0
0
a^4
a^3
a^2
a
1
0
 
What's an efficient way to do this? (this matrix being KxK, K very
large)
 
Thanks
 
Zava
--------------------------------------------------------

This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}

You might want to check lower.tri. Also, keep in mind that a matrix
in R is just a vector with a 'dim' attribute. The elements are stored 
columnwise.

Gabor

On Thu, Jul 05, 2007 at 06:53:45PM -0400, Aydemir, Zava (FID)
wrote:
> Hi,
>  
> I would like to generate below triangular matrix for some  a.
>  
> 0
> 0
> 0
> 0
[...]
>  
> What's an efficient way to do this? (this matrix being KxK, K very
> large)
>  
> Thanks
>  
> Zava
> --------------------------------------------------------
> 
> This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
> 
> ______________________________________________
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-- 
Csardi Gabor <csardi at rmki.kfki.hu>    MTA RMKI, ELTE TTK