In R, when using named rows, can a sparse matrix column be added to another sparse matrix?
- by ayman
I have two sparse matrices, m1 and m2:
> m1 <- Matrix(data=0,nrow=2, ncol=1, sparse=TRUE, dimnames=list(c("b","d"),NULL))
> m2 <- Matrix(data=0,nrow=2, ncol=1, sparse=TRUE, dimnames=list(c("a","b"),NULL))
> m1["b",1]<- 4
> m2["a",1]<- 5
> m1
2 x 1 sparse Matrix of class "dgCMatrix"
b 4
d .
> m2
2 x 1 sparse Matrix of class "dgCMatrix"
a 5
b .
>
and I want to cbind() them to make a sparse matrix like:
[,1] [,2]
a . 5
b 4 .
d . .
however cbind() ignores the named rows:
> cbind(m1[,1],m2[,1])
[,1] [,2]
b 4 5
d 0 0
is there some way to do this without a brute force loop?
