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Create a color gradient (color-bar) legend specification

Source: R/legend.R
seq_gradient_legend.Rd

Constructs a GradientLegendSpec describing a continuous color-scale legend (color bar). When breaks is supplied the bar is rendered as discrete LegendKey entries instead — useful for heatmaps that need only a handful of labelled stops.

Usage

seq_gradient_legend(
  palette = "viridis",
  limits = c(0, 1),
  title = NULL,
  position = "inside",
  x = 0.5,
  y = 0.5,
  hjust = 0,
  orientation = NULL,
  side = NULL,
  breaks = NULL
)

Arguments

palette

One of "viridis", "plasma", "magma", "blues", "reds". Default "viridis".

limits

Numeric vector of length 2. The data range the gradient spans. Default c(0, 1).

title

Optional character string. Legend group title.

position

One of "inside", "track_margin", "canvas_margin".

x, y

Numeric in [0, 1]. Anchor of the bar within the target area. Default 0.5.

hjust

Horizontal justification of the bar relative to the anchor. Default 0.

orientation

"horizontal" or "vertical". Bar direction. Inferred from side when NULL.

side

For margin positions: one of "top", "bottom", "left", "right". Defaults to "top" for margin positions.

breaks

NULL (continuous color bar), a single positive integer (that many evenly-spaced discrete keys), or a numeric vector of explicit break values.

Value

A GradientLegendSpec S3 object.

Examples

# Continuous color bar
seq_gradient_legend(palette = "viridis", limits = c(0, 100), title = "Score")
#> <GradientLegendSpec> palette=viridis  limits=[0, 100]  position=inside  side=NULL  breaks=NULL (continuous)  title="Score"

# Five discrete keys
seq_gradient_legend(palette = "plasma", limits = c(-2, 2), breaks = 5)
#> <GradientLegendSpec> palette=plasma  limits=[-2, 2]  position=inside  side=NULL  breaks=n=5 discrete