R help - Dec 2004 - how to make the matrix as factors

Hi All,

Thanks for you help, I have loaded the library MASS to call the mca. But when I
want to do the mca, there is another problem, for example
--------
--------
> leaf <- read.table("C:/Documents and
Settings/wxh-c/×ÀÃæ/1.txt",
+
col.names=c("size","texture"),header=TRUE)
> leaf
    size texture
1      3       3
2      2       2
3      3       2
4      3       2
5      3       2
6      3       3
7      3       2
8      3       2
9      3       2
> attach(leaf)
> require(MASS)
Loading required package: MASS 
[1] TRUE
> new.mca <- mca(leaf)
Error in mca(leaf) : All variables must be factors
---------
So, what should I do to make the matrix as factor. Waiting for you answers.
Thanks!

                                                                jeff

Hi,

The argument df of the function 'mca?? requires only a data.frame (not
matrix)
containing only factors.


# Example:
?data.frame

library(MASS)
?mca

# we  construct the matrix.
size <- c(3,2,3,3,3,3,3,3,3)
texture <- c(2,3,2,2,2,2,2,2,2)
leaf <- cbind(size,texture)

new.mca <- mca(leaf)

# Error in mca(leaf) : All variables must be factors

# now, we construct a data.frame.
dleaf <- as.data.frame(leaf)
summary(dleaf)

# we transform each variable into a factor. 
dleaf[,2] <- as.factor(dleaf[,2])
dleaf[,1] <- as.factor(dleaf[,1])
summary(dleaf)
new.mca <- mca(dleaf)
new.mca
#

cheers,


P.BADY





En r??ponse ?? ys03165003 at student.ecnu.edu.cn:
> Hi All,
> 
> Thanks for you help, I have loaded the library MASS to call the mca. But
> wen I
> want to do the mca, there is another problem, for example
> --------
> --------
> > leaf <- read.table("C:/Documents and
Settings/wxh-c/????????/1.txt",
> + col.names=c("size","texture"),header=TRUE)
> > leaf
>     size texture
> 1      3       3
> 2      2       2
> 3      3       2
> 4      3       2
> 5      3       2
> 6      3       3
> 7      3       2
> 8      3       2
> 9      3       2
> > attach(leaf)
> > require(MASS)
> Loading required package: MASS 
> [1] TRUE
> > new.mca <- mca(leaf)
> Error in mca(leaf) : All variables must be factors
> ---------
> So, what should I do to make the matrix as factor. Waiting for you
> answers.
> Thanks!
> 
>                                                                 jeff
> 
> ______________________________________________
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> 
> 


---------------------------------------------------------
Pierre BADY     <??)))><
Universit?? Claude Bernard Lyon 1
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