R help - Mar 2005 - Binding one column of characters into a dataframe factors other numeric columns

Hi all,

I searched through the archives, but couldn't find a fix...

Basically, I've got a bunch of numeric vectors and one character vector that
I want to bind into a data frame. When I include the character vector as a 
column in the data frame, all the numeric columns get factored in the data 
frame, which makes it tough to call those columns for calculations later on. 
I've tried using AsIs to prevent this, but without luck...in the examples 
below, the object named "c" is the one that is the character column.
The
others are numeric.

df_without_char <- data.frame(cbind(rl, gl, cp), row.names = rownames(r)) 
#without char vector

df_without_char <- data.frame(cbind(rl, gl, c, cp), row.names = 
rownames(r))#with char vector

df <- data.frame(cbind(rl, gl, I(c), cp), row.names = rownames(r)) #try to 
keep char vector AsIs

df <- data.frame(cbind(rl, gl, c=I(c), cp), row.names = rownames(r)) #try to 
keep char vector AsIs

df <- data.frame(cbind(rl, gl, c, I(cp)), row.names = rownames(r)) #try to 
keep num vector AsIs

df <- data.frame(cbind(rl, gl,  c, cp=I(cp)), row.names = rownames(r)) #try 
to keep num vector AsIs


Thanks in advance,
Ken

On Thu, 2005-03-17 at 18:30 +0000, Ken Termiso wrote:
> Hi all,
> 
> I searched through the archives, but couldn't find a fix...
> 
> Basically, I've got a bunch of numeric vectors and one character vector
that
> I want to bind into a data frame. When I include the character vector as a 
> column in the data frame, all the numeric columns get factored in the data 
> frame, which makes it tough to call those columns for calculations later
on.
> I've tried using AsIs to prevent this, but without luck...in the
examples
> below, the object named "c" is the one that is the character
column. The
> others are numeric.
> 
> df_without_char <- data.frame(cbind(rl, gl, cp), row.names =
rownames(r))
> #without char vector
> 
> df_without_char <- data.frame(cbind(rl, gl, c, cp), row.names = 
> rownames(r))#with char vector
> 
> df <- data.frame(cbind(rl, gl, I(c), cp), row.names = rownames(r)) #try
to
> keep char vector AsIs
> 
> df <- data.frame(cbind(rl, gl, c=I(c), cp), row.names = rownames(r))
#try to
> keep char vector AsIs
> 
> df <- data.frame(cbind(rl, gl, c, I(cp)), row.names = rownames(r)) #try
to
> keep num vector AsIs
> 
> df <- data.frame(cbind(rl, gl,  c, cp=I(cp)), row.names = rownames(r))
#try
> to keep num vector AsIs

Don't use cbind() on all vectors, which will initially create a matrix
using a single data type.

Just list each vector separately. Try this:

rl <- 1:5
gl <- 6:10
cp <- 11:15
c <- letters[1:5]

df <- data.frame(rl, gl, cp, c)
> df
  rl gl cp c
1  1  6 11 a
2  2  7 12 b
3  3  8 13 c
4  4  9 14 d
5  5 10 15 e
> str(df)
`data.frame':	5 obs. of  4 variables:
 $ rl: int  1 2 3 4 5
 $ gl: int  6 7 8 9 10
 $ cp: int  11 12 13 14 15
 $ c : Factor w/ 5 levels
"a","b","c","d",..: 1 2 3 4 5


If you do not want 'c' to become a factor, you can use I() like this:

df <- data.frame(rl, gl, cp, I(c))
> str(df)
`data.frame':	5 obs. of  4 variables:
 $ rl: int  1 2 3 4 5
 $ gl: int  6 7 8 9 10
 $ cp: int  11 12 13 14 15
 $ c :Class 'AsIs'  chr [1:5] "a" "b" "c"
"d" ...


You can of course still use the "row.names" argument as you are to set
the rownames in the data frame.


HTH,

Marc Schwartz