[R] Question about rpart and regression trees

[Paul Smith]

Dear All

I would like to use rpart to obtain a regression tree for a dataset
like the following:

Y	X1	X2	X3	X4
5.500033	B	A	3	2
0.35625148	D	B	6	5
0.8062546	E	C	4	3
5.100014	C	A	3	2
5.7000422	A	A	3	2
0.76875436	C	A	6	5
1.0312537	D	A	4	1

Y is the objective variable. X1, X2, X3 and X4 can take, respectively,
the following values:

X1: A,B,C,D,E
X2: A,B,C,D,E
X3: 3,4,5,6
X4. 1,2,3,4,5

Should I convert X3 and X4 to factor before running rpart?

Thanks in advance,

Paul