In R, it is not possible to use binary operations, like -, on the
lines of a data frame, even if all columns contain numeric values. In
Splus this is possible:
R> a<-data.frame(int1=3D1:3,int2=3D4:6)
R> a[1,]-a[2,]
Error in a[1, ] - a[2, ] : non-numeric argument to binary operator
but
S> a<-data.frame(int1=3D1:3,int2=3D4:6)
S> a[1,]-a[2,]
int1 int2=20
1 -1 -1
If not all columns contain numeric values, both R and S give an error:
R>
b<-data.frame(int1=3D1:3,int2=3D4:6,char=3Dc("a","b","c"))
R> b[1,]-b[2,]
Error in b[1, ] - b[2, ] : non-numeric argument to binary operator
S>
b<-data.frame(int1=3D1:3,int2=3D4:6,char=3Dc("a","b","c"))
S> b[1,]-b[2,]
Error in Ops.factor(e1, e2): "-" not meaningful for factors
Dumped
but the following is again different:
R>
b<-data.frame(int1=3D1:3,int2=3D4:6,char=3Dc("a","b","c"))
R> b[1,1:2]-b[2,1:2]
Error in b[1, 1:2] - b[2, 1:2] : non-numeric argument to binary operator
S>
b<-data.frame(int1=3D1:3,int2=3D4:6,char=3Dc("a","b","c"))> b[1,1:2]-b[2,1:2]
int1 int2=20
1 -1 -1
************************************************************************
* Andreas Weingessel *
************************************************************************
* Institut f=FCr Statistik * Tel: (+43 1) 58801 4541 *
* Technische Universit=E4t Wien * Fax: (+43 1) 504 14 98 *
* Wiedner Hauptstr. 8-10/1071 * Andreas.Weingessel@ci.tuwien.ac.at *
* A-1040 Wien, Austria * http://www.ci.tuwien.ac.at/~weingessel *
************************************************************************
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To:
r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._