label_basepair: Label numbers as basepairs with SI suffix
In teunbrand/ggnomics: ggnomics

Description Usage Arguments Details Value Examples

basepair_label() automatically scales and labels numbers with an appropriate SI suffix, e.g. "kb" for values ≥ 1e3, "Mb" for ≥ 1e6, "Gb" for ≥ 1e9.

label_basepair(
  accuracy = NULL,
  unit = "b",
  sep = NULL,
  labelsmall = FALSE,
  ...
)

basepair_label(x)

`accuracy`	A number to round to. Use (e.g.) `0.01` to show 2 decimal places of precision. If `NULL`, the default, uses a heuristic that should ensure breaks have the minimum number of digits needed to show the difference between adjacent values. Applied to rescaled data.
`unit`	Optional units specifier.
`sep`	Separator between number and SI unit. Defaults to `" "` if `units` is supplied, and `""` if not.
`labelsmall`	A `logical` wether of not append the suffix to values smaller than 1000 (default: `FALSE`).
`...`	Other arguments passed on to `base::format()`.
`x`	A vector to label. Can either be `numeric` of inherit from GenomicRanges, in which case takes the start positions to label.

The label_basepair() function is a function factory that returns a labelling function, i.e. a function that takes a vector x and returns a character vector of length(x) giving a label for each input value. The basepair_label() function is the default labeller from label_basepair() for convenience.

Note that these functions don't attempt to format numbers smaller than 1, as the units millibasepair and centibasepairs do not make sense.

When used in combination with scale_(x|y)_genomic, these labelling functions work best as the minor_labels argument.

A function for label_basepair() or a character vector of labels for basepair_label().

require(scales)

# The following labels are equivalent
demo_continuous(c(1, 1e9), label = label_basepair())
demo_continuous(c(1, 1e9), label = basepair_label)

# When the label 'bp' is preffered over 'b'
demo_continuous(c(1, 1e9), label = label_basepair(unit = "bp"))