I would like to create a block diagonal matrix with the diagonal blocks being repeated a certain number of times, with the off-diagonal blocks being all zero matrices. For example, suppose we start with a matrix with the following:
> diag.matrix
[,1] [,2] [,3] [,4] [,5]
[1,] 1.0 0.5 0.5 0.5 0.5
[2,] 0.5 1.0 0.5 0.5 0.5
[3,] 0.5 0.5 1.0 0.5 0.5
[4,] 0.5 0.5 0.5 1.0 0.5
[5,] 0.5 0.5 0.5 0.5 1.0
I would like this matrix to be the diagonal block matrix so that in the end I have something like:
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10]
[1,] 1.0 0.5 0.5 0.5 0.5 0.0 0.0 0.0 0.0 0.0
[2,] 0.5 1.0 0.5 0.5 0.5 0.0 0.0 0.0 0.0 0.0
[3,] 0.5 0.5 1.0 0.5 0.5 0.0 0.0 0.0 0.0 0.0
[4,] 0.5 0.5 0.5 1.0 0.5 0.0 0.0 0.0 0.0 0.0
[5,] 0.5 0.5 0.5 0.5 1.0 0.0 0.0 0.0 0.0 0.0
[6,] 0.0 0.0 0.0 0.0 0.0 1.0 0.5 0.5 0.5 0.5
[7,] 0.0 0.0 0.0 0.0 0.0 0.5 1.0 0.5 0.5 0.5
[8,] 0.0 0.0 0.0 0.0 0.0 0.5 0.5 1.0 0.5 0.5
[9,] 0.0 0.0 0.0 0.0 0.0 0.5 0.5 0.5 1.0 0.5
[10,] 0.0 0.0 0.0 0.0 0.0 0.5 0.5 0.5 0.5 1.0
Here, we have the same block matrix above repeated twice in the block diagonals. If I wanted to do this efficiently an arbitrary number of times, is there a way to do it? thanks!