geom_timeline: Add Timeline Plot
In dtminnick/earthquake: NOAA Significant Earthquake Analysis

Description Usage Arguments Details Aesthetics Examples

View source: R/eq_geoms.R

geom_timeline plots a timeline with points showing the dates when earthquakes occurred. The color of the points corresponds to the number of deaths associated with an event and the size of the point corresponds to the magnitude of the earthquake (higher magnitude creates a larger point).

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geom_timeline(mapping = NULL, data = NULL, stat = "identity",
  position = "identity", na.rm = FALSE, show.legend = NA,
  inherit.aes = TRUE, xmin = NULL, xmax = NULL, ...)

`mapping`	Set of aesthetic mappings created by `aes()` or `aes_()`. If specified and `inherit.aes = TRUE` (the default), it is combined with the default mapping at the top level of the plot. You must supply `mapping` if there is no plot mapping.
`data`	The data to be displayed in this layer. There are three options: If `NULL`, the default, the data is inherited from the plot data as specified in the call to `ggplot()`. A `data.frame`, or other object, will override the plot data. All objects will be fortified to produce a data frame. See `fortify()` for which variables will be created. A `function` will be called with a single argument, the plot data. The return value must be a `data.frame`, and will be used as the layer data.
`stat`	The statistical transformation to use on the data for this layer, as a string.
`position`	Position adjustment, either as a string, or the result of a call to a position adjustment function.
`na.rm`	If `FALSE`, the default, missing values are removed with a warning. If `TRUE`, missing values are silently removed.
`show.legend`	logical. Should this layer be included in the legends? `NA`, the default, includes if any aesthetics are mapped. `FALSE` never includes, and `TRUE` always includes. It can also be a named logical vector to finely select the aesthetics to display.
`inherit.aes`	If `FALSE`, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. `borders()`.
`xmin`	A Date object identifying the earliest date include in the timeline plot.
`xmax`	A Date object identifying the latest date to include in the timeline plot.
`...`	Other arguments passed on to `layer()`. These are often aesthetics, used to set an aesthetic to a fixed value, like `colour = "red"` or `size = 3`. They may also be parameters to the paired geom/stat.

This geom is designed to be used with the NOAA Significant Earthquake data set but it can show any data with a data frame of valid date objects.

Each earthquake event with an associated date will be plotted as a circle on the timeline as long as the event occurs between xmin and xmax.

Additional optional aesthetics can make the geom more useful. The y aesthetic allows a comparison of two or more timelines over the same date range, e.g. comparing events for two countries. Size can be used to show the magnitude of events and color, fill or alpha can convey number of deaths.

geom_timeline understands the following aesthetics (required aesthetics in bold):

x
y
]codecolor
fill
size
alpha

## Not run: 
ggplot(data = earthquakes, aes(x = DATE)) +
     geom_timeline(xmin = "2000-01-01", xmax = "2018-12-31",
                   aes(color = TOTAL_DEATHS, size = EQ_PRIMARY))

The following example includes the \code{y} aesthetic to plot timelines
for each country in the data frame.

ggplot(data = earthquakes, aes(x = DATE, y = COUNTRY)) +
     geom_timeline(xmin = "2000-01-01", xmax = "2018-12-31",
                   aes(color = TOTAL_DEATHS, size = EQ_PRIMARY))

## End(Not run)