Position scales for date/time data

Source: R/scale-date.r

These are the default scales for the three date/time class. These will usually be added automatically. To override manually, use scale_*_date for dates (class Date), scale_*_datetime for datetimes (class POSIXct), and scale_*_time for times (class hms).

scale_x_date(name = waiver(), breaks = waiver(), date_breaks = waiver(),
  labels = waiver(), date_labels = waiver(), minor_breaks = waiver(),
  date_minor_breaks = waiver(), limits = NULL, expand = waiver(),
  position = "bottom")

scale_y_date(name = waiver(), breaks = waiver(), date_breaks = waiver(),
  labels = waiver(), date_labels = waiver(), minor_breaks = waiver(),
  date_minor_breaks = waiver(), limits = NULL, expand = waiver(),
  position = "left")

scale_x_datetime(name = waiver(), breaks = waiver(),
  date_breaks = waiver(), labels = waiver(), date_labels = waiver(),
  minor_breaks = waiver(), date_minor_breaks = waiver(), timezone = NULL,
  limits = NULL, expand = waiver(), position = "bottom")

scale_y_datetime(name = waiver(), breaks = waiver(),
  date_breaks = waiver(), labels = waiver(), date_labels = waiver(),
  minor_breaks = waiver(), date_minor_breaks = waiver(), timezone = NULL,
  limits = NULL, expand = waiver(), position = "left")

scale_x_time(name = waiver(), breaks = waiver(), minor_breaks = waiver(),
  labels = waiver(), limits = NULL, expand = waiver(), oob = censor,
  na.value = NA_real_, position = "bottom")

scale_y_time(name = waiver(), breaks = waiver(), minor_breaks = waiver(),
  labels = waiver(), limits = NULL, expand = waiver(), oob = censor,
  na.value = NA_real_, position = "left")

Arguments

name

The name of the scale. Used as axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted.
breaks

One of:

  • NULL for no breaks

  • waiver() for the breaks specified by date_breaks

  • A Date/POSIXct vector giving positions of breaks

  • A function that takes the limits as input and returns breaks as output
date_breaks

A string giving the distance between breaks like "2 weeks", or "10 years". If both breaks and date_breaks are specified, date_breaks wins.
labels

One of:

  • NULL for no labels

  • waiver() for the default labels computed by the transformation object

  • A character vector giving labels (must be same length as breaks)

  • A function that takes the breaks as input and returns labels as output
date_labels

A string giving the formatting specification for the labels. Codes are defined in strftime(). If both labels and date_labels are specified, date_labels wins.
minor_breaks

One of:

  • NULL for no breaks

  • waiver() for the breaks specified by date_minor_breaks

  • A Date/POSIXct vector giving positions of minor breaks

  • A function that takes the limits as input and returns minor breaks as output
date_minor_breaks

A string giving the distance between minor breaks like "2 weeks", or "10 years". If both minor_breaks and date_minor_breaks are specified, date_minor_breaks wins.
limits

A numeric vector of length two providing limits of the scale. Use NA to refer to the existing minimum or maximum.
expand

Vector of range expansion constants used to add some padding around the data, to ensure that they are placed some distance away from the axes. Use the convenience function expand_scale() to generate the values for the expand argument. The defaults are to expand the scale by 5% on each side for continuous variables, and by 0.6 units on each side for discrete variables.
position

The position of the axis. "left" or "right" for vertical scales, "top" or "bottom" for horizontal scales
timezone

The timezone to use for display on the axes. The default (NULL) uses the timezone encoded in the data.
oob

Function that handles limits outside of the scale limits (out of bounds). The default replaces out of bounds values with NA.
na.value

Missing values will be replaced with this value.

See also

Other position scales: scale_x_continuous, scale_x_discrete

Examples

last_month <- Sys.Date() - 0:29
df <- data.frame(
  date = last_month,
  price = runif(30)
)
base <- ggplot(df, aes(date, price)) +
  geom_line()

# The date scale will attempt to pick sensible defaults for
# major and minor tick marks. Override with date_breaks, date_labels
# date_minor_breaks arguments.
base + scale_x_date(date_labels = "%b %d")
base + scale_x_date(date_breaks = "1 week", date_labels = "%W")
base + scale_x_date(date_minor_breaks = "1 day")

# Set limits
base + scale_x_date(limits = c(Sys.Date() - 7, NA))
#> Warning: Removed 22 rows containing missing values (geom_path).