### A{i,j} B{j,k}
a <- array(letters[1:6], dim = c(i=2, j=3))
b <- array(letters[1:3], dim = c(j=3, k=1))
einstein(a,b)
### A{i,j} B{j,k,k} C{k,l} D{j,k}
a <- array(1:10, dim = c(i=2, j=5))
b <- array(1:45, dim = c(j=5, k=3, k=3))
c <- array(1:12, dim = c(k=3, l=4))
d <- array(1:15, dim = c(j=5, k=3))
einstein(a,b,c,d)
Run the code above in your browser using DataLab