bdiag {Matrix} | R Documentation

## Construct a Block Diagonal Matrix

### Description

Build a block diagonal matrix given several building block matrices.

### Usage

    bdiag(...)

### Arguments

`...` | individual matrices or a `list` of matrices.

### Value

A sparse matrix inheriting from class `CsparseMatrix` obtained by combining the arguments into a block diagonal matrix.

### Author(s)

Martin Maechler, built on a version posted by Berton Gunter to R-help; earlier versions have been posted by other authors, notably Scott Chasalow to S-news. Doug Bates's faster implementation builds on `TsparseMatrix` objects.

### See Also

`Diagonal` for constructing matrices of class `diagonalMatrix`, or `kronecker` which also works for `"Matrix"` inheriting matrices.

`bandSparse` constructs a banded sparse matrix from its non-zero sub-/super - diagonals.

Note that other CRAN R packages have own versions of `bdiag()` which return traditional matrices.

### Examples

    bdiag(matrix(1:4, 2), diag(3))
    ## combine "Matrix" class and traditional matrices:
    bdiag(Diagonal(2), matrix(1:3, 3,4), diag(3:2))

    mlist <- list(1, 2:3, diag(x=5:3), 27, cbind(1,3:6), 100:101)
    bdiag(mlist)

    stopifnot(identical(bdiag(mlist),
                        bdiag(lapply(mlist, as.matrix))))

[Package Matrix version 0.999375-33 Index]