sfsmisc (version 0.9-4)

diagX: The ``Other'' Diagonal Matrix

Description

Compute the other diagonal identity matrix. The result is basically a fast version of diag(n)[, n:1].

Usage

diagX(n)

Arguments

n

positive integer.

Value

• a numeric $n \times n$ matrix with many zeros -- apart from 1s in the other diagonal.

See Also

diag.

Examples

diagX(4)
for(m in 1:5)
  stopifnot(identical(diagX(m), diag(m)[, m:1, drop = FALSE]))