Standard deviation of an interval-valued variable

The square root of tda_ivariance's bounds – valid because the square root is monotone. Its own function because a variance function printing standard deviations surprised people, reasonably.

Usage

tda_isd(formula, data, ...)

Arguments

formula, data, ...

as in tda_ivariance.

Value

A named vector, the lower and upper standard deviation.

Examples

d <- data.frame(lo = c(1, 3, 5, 9), hi = c(2, 4, 8, 12))
tda_isd(~ iv(lo, hi), d)
#>    lower    upper 
#> 2.549510 4.301163