[R] Way to convert data frame to matrix

Sarah Goslee sarah.goslee at gmail.com
Fri Jun 30 16:33:21 CEST 2006

Hi Wade,

On 6/30/06, Wade Wall <wade.wall at gmail.com> wrote:
>   I have a text file that I have imported into R.  It contains 3 columns and
> 316940 rows.  The first column is vegetation plot ID, the second species
> names and the third is a cover value (numeric).  I imported using the
> read.table function.
> My problem is this.  I need to reformat the information as a matrix, with
> the first column becoming the row labels and the second the column labels
> and the cover values as the matrix cell data.

Try crosstab(mydata$plotID, mydata$species, mydata$cover) from the
ecodist package.

Sarah Goslee

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