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

A numeric vector of length 2, r + c(-f,f) * diff(r).

See Also

range; pretty which can be considered a sophisticated extension of extendrange.

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)))

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