Re: [R] Make matrix from SQL query result

From: Patrick Burns <pburns_at_pburns.seanet.com>
Date: Sat 25 Jun 2005 - 03:15:49 EST

Gilbert,

This is untested, but something like:

function(x) {

    uniq.col <- unique(x[,1])
    uniq.row <- unique(x[,2])
    ans <- array(NA, c(length(uniq.row), length(uniq.col)), 
list(uniq.row, uniq.col))

    ans[cbind(match(x[,2], uniq.row), match(x[,1], uniq.col))] <- x[,3]     ans
}

Pat

Gilbert Wu wrote:

>Hi,
>
>I am trying to form a matrix from a SQL query result.
>
>The SQL query result looks like this:
>
>equity_id date returns
>1 20050619 0.12
>2 20050619 0.03
>1 20050620 -0.01
>2 20050620 0.01
>
>The target matrix looks like this:
>
>
>date 1 2
>20050619 0.12 0.03
>20050620 -0.01 0.01
>
>Any suggestion would be much appreciated.
>
>Many Thanks.
>
>Gilbert
>
> [[alternative HTML version deleted]]
>
>______________________________________________
>R-help@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
>
>
>
>
>



R-help@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 Received on Sat Jun 25 03:29:17 2005

This archive was generated by hypermail 2.1.8 : Fri 03 Mar 2006 - 03:33:02 EST