R: Extend a Numerical Range by a Small Percentage

extendrange {grDevices}

R Documentation

Extend a Numerical Range by a Small Percentage

Description

Extends a numerical range by a small percentage, i.e., fraction, on both sides.

Usage

extendrange(x, r = range(x, na.rm = TRUE), f = 0.05)

Arguments

`x`	numeric vector; not used if `r` is specified.
`r`	numeric vector of length 2; defaults to the `range` of `x`.
`f`	number specifying the fraction by which the range should be extended.

Value

numeric vector of length 2, “r extended”, namely simply r + c(-f,f) * diff(r).

Examples

x <- 1:5
(r <- range(x))         # 1    5
extendrange(x)          # 0.8  5.2
extendrange(x, f= 0.01) # 0.96 5.04
## Use 'r' if you have it already:
stopifnot(identical(extendrange(r=r),
                    extendrange(x)))