Returns a matrix of logicals the same size of a given matrix with entries 'TRUE' in the upper triangle close to the diagonal.

diag.ind(x, n = 1, diag = TRUE)

## Arguments

x a matrix. the number of elements from the diagonal to include. logical. Should the diagonal be included?

## Details

Basic function useful for masking elements close to the diagonal of a given matrix.

## Value

Returns a matrix of logicals the same size of a given matrix with entries 'TRUE' in the upper triangle close to the diagonal.

## References

Grant, B.J. et al. (2006) Bioinformatics 22, 2695--2696.

## Author

Barry Grant

diag, lower.tri, upper.tri, matrix
diag.ind( matrix(,ncol=5,nrow=5), n=3 )
#> [5,] FALSE FALSE FALSE FALSE  TRUE