Creating a multiplication matrix from data frame

Question

I have this matrix

m<- matrix(c(0:13),nrow=2,ncol=7)
colnames(m)<-c("0","1","2","3","4","5","6")
rownames(m)<-c("A","B")


  0 1 2 3 4  5  6
A 0 2 4 6 8 10 12
B 1 3 5 7 9 11 13

and I want to multiply each observation in row one by each observation in row two. So I would have something that looks like this

   0  1  2  3  4  5  6
0 NA NA NA NA NA NA NA
1 NA NA NA NA NA NA NA
2 NA NA NA NA NA NA NA
3 NA NA NA NA NA NA NA
4 NA NA NA NA NA NA NA
5 NA NA NA NA NA NA NA
6 NA NA NA NA NA NA NA

score 0 · Accepted Answer · answered Nov 17 '14 at 18:26

0

Try

outer(m[1,], m[2,], FUN='*')

or

as.matrix(m[1,])%*% m[2,]

answered Nov 17 '14 at 18:26

akrun

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Creating a multiplication matrix from data frame

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