position_disjoint_ranges: Segregating overlapping ranges

In ggh4x: Hacks for 'ggplot2'

Segregating overlapping ranges

Description

One-dimensional ranged data in the x-direction is segregated in the y-direction such that no overlap in two-dimensional space occurs. This positioning works best when no relevant information is plotted in the y-direction.

Usage

position_disjoint_ranges(extend = 1, stepsize = 1)

Arguments

extend	a numeric of length 1 indicating how far a range should be extended in total for calculating overlaps. Setting this argument to a positive number leaves some space between ranges in the same bin.
stepsize	a numeric of length 1 that determines how much space is added between bins in the y-direction. A positive value grows the bins from bottom to top, while a negative value grows the bins from top to bottom.

Details

An object is considered disjoint from a second object when the range between their xmin and xmax coordinates don't overlap. Objects that overlap are assigned to different bins in the y-direction, whereby lower bins are filled first. This way, information in the x-direction is preserved and different objects can be discerned.

Note that this positioning is only particularly useful when y-coordinates do not encode relevant information. Geoms that pair well with this positioning are geom_rect() and ggplot2::geom_tile().

This positioning function was inspired by the disjointBins() function in the IRanges package, but has been written such that it accepts any numeric input next to solely integer input.

Value

A PositionDisjointRanges object.

See Also

The disjointBins function the Bioconductor IRanges package.

Examples

# Even though geom_tile() is parametrised by middle-x values, it is
# internally converted to xmin, xmax, ymin, ymax parametrisation so the
# positioning still works.

ggplot() +
  geom_tile(aes(x = rnorm(200), y = 0),
            width = 0.2, height = 0.9,
            position = position_disjoint_ranges(extend = 0.1))

ggh4x documentation built on Aug. 31, 2023, 1:08 a.m.