bldiag {metafor}

Construct Block Diagonal Matrix

Description

Function to construct a block diagonal matrix from (a list of) matrices.

Usage

bldiag(..., order)

Arguments

...

individual matrices or a list of matrices.

order

optional argument to specify a variable based on which a square block diagonal matrix should be ordered.

Author(s)

Posted to R-help by Berton Gunter (2 Sep 2005) with some further adjustments by Wolfgang Viechtbauer

See Also

rma.mv for the model fitting function that can take such a block diagonal matrix as input (for the V argument).

blsplit for a function that can split a block diagonal matrix into a list of sub-matrices.

Examples

### copy data into 'dat'
dat <- dat.berkey1998
dat

### construct list with the variance-covariance matrices of the observed outcomes for the studies
V <- lapply(split(dat[c("v1i","v2i")], dat$trial), as.matrix)
V

### construct block diagonal matrix
V <- bldiag(V)
V

### if we split based on 'author', the list elements in V are in a different order than tha data
V <- lapply(split(dat[c("v1i","v2i")], dat$author), as.matrix)
V

### can use 'order' argument to reorder the block-diagonal matrix into the correct order
V <- bldiag(V, order=dat$author)
V