# [R] factor matrix

Mulholland, Tom Tom.Mulholland at dpi.wa.gov.au
Fri Dec 3 08:13:51 CET 2004

```This is my playing about

The last one is a matrix of factors of dimension 2 by 2. It;s just that it does not look that way.

> tt <- matrix(as.numeric(factor(c(T,F,F,T))), 2,2)
> str(tt)
num [1:2, 1:2] 2 1 1 2
> tt <- matrix((factor(c(T,F,F,T))), 2,2)
> str(tt)
chr [1:2, 1:2] "TRUE" "FALSE" "FALSE" "TRUE"
> tt <- c(T,F,F,T)
> str(tt)
logi [1:4]  TRUE FALSE FALSE  TRUE
> dim(tt) <- c(2,2)
> str(tt)
logi [1:2, 1:2]  TRUE FALSE FALSE  TRUE
> tt <- factor(c(T,F,F,T))
> dim(tt) <- c(2,2)
> str(tt)
factor [1:2, 1:2] TRUE FALSE FALSE TRUE
- attr(*, "levels")= chr [1:2] "FALSE" "TRUE"
- attr(*, "class")= chr "factor"
> tt
[1] TRUE  FALSE FALSE TRUE
Levels: FALSE TRUE
>

> -----Original Message-----
> Sent: Friday, 3 December 2004 2:44 PM
> To: Mulholland, Tom
> Cc: r-help at stat.math.ethz.ch
> Subject: RE: [R] factor matrix
>
>
>
> > matrix(as.numeric(factor(c(T,F,F,T))), 2,2)
>
> No, this produces a matrix with numeric values,
> not categorical values.
>
>
>

```