[R] Array

[Bronagh Grimes]

Thanks for this, will have a look now.

Much appreciated,

-----Original Message-----
From: Peter Dalgaard [mailto:P.Dalgaard at biostat.ku.dk] 
Sent: 24 April 2009 11:40
To: Bronagh Grimes
Cc: r-help at r-project.org
Subject: Re: [R] Array

Bronagh Grimes wrote:

> Just wondering if anyone has any tips for using arrays?

You're presupposing that R works like SAS. It doesn't.

This looks like a job for reshape (either Hadley Wickham's package or
the built-in function).

> I am trying to convert the following SAS code to R: 

> data A2;  
>  set A1;   
>  by subject_id;
>  retain   BX1-BX10    i; 
>  array b(1:10) BX1-BX10 ;
>  if first.subject_id then do ;
>       do j=1 to 10;
>        b(j) = .;    
>       end;
>       i=1;
>  end;
>  b(i)  =  BX;
>  i = i+1;
>  if last.subject_id then output;
> run ;

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