Skip to contents

These functions are helper functions for working with keys in guides. The functions described here are not widely applicable and may only apply to a small subset of guides. As such, it is fine to adjust the arguments of a speciality key, but swapping types is ill-advised.

  • key_sequence() is a function factory whose functions create a regularly spaced sequence between the limits of a scale. It is used in colour bar guides.

  • key_bins() is a function factory whose function create a binned key given the breaks in the scale. It is used in colour steps guides.

Usage

key_sequence(n = 15)

key_bins(even.steps = FALSE, show.limits = NULL)

Arguments

n

A positive <integer[1]> giving the number of colours to use for a gradient.

even.steps

A <logical[1]> indicating whether the size of bins should be displayed as equal (TRUE) or proportional to their length in data space (FALSE).

show.limits

A <logical[1]> stating whether the limits of the scale should be shown with labels and ticks (TRUE) or remain hidden (FALSE). Note that breaks coinciding with limits are shown regardless of this setting. The default, NULL, consults the scale's show.limits setting or defaults to FALSE.

Value

For key_sequence() a function.

See also

Other keys: key_range, key_standard

Examples

# An example scale
template <- scale_fill_viridis_c(limits = c(0, 10), breaks = c(2, 4, 6, 8))

# Retrieving colourbar and colourstep keys
key_sequence()(template)
#>       fill     .value
#> 1  #440154  0.0000000
#> 2  #461F66  0.7142857
#> 3  #453478  1.4285714
#> 4  #414888  2.1428571
#> 5  #3C5B8A  2.8571429
#> 6  #336D8D  3.5714286
#> 7  #2B7F8D  4.2857143
#> 8  #2B9089  5.0000000
#> 9  #26A186  5.7142857
#> 10 #40B17B  6.4285714
#> 11 #5FBF69  7.1428571
#> 12 #76CE56  7.8571429
#> 13 #A4D848  8.5714286
#> 14 #D2E039  9.2857143
#> 15 #FDE725 10.0000000
key_bins()(template)
#>      fill min max .label .value
#> 1 #46286D   0   2   <NA>     NA
#> 2 #3B5E8B   2   4      2      2
#> 3 #2B9089   4   6      4      4
#> 4 #5ABC6D   6   8      6      6
#> 5 #C0DD40   8  10      8      8
#> 6    <NA>  NA  NA   <NA>     NA