geom_timeline_label: Labels for earthquake timeline plot

In davidbody/earthquakes-package: Earthquakes Package for Mastering Software Development in R Capstone

Description

This geom is intended to be used in conjunction with the geom_timeline geom to add a vertical line with a text annotation (e.g. the location of the earthquake) for each data point on an earthquake timeline. The x aesthetic specifies the date of the earthquake and the label aesthetic specifies the label for the annotation. An optional n_max aesthetic can be used to subset to n_max earthquakes, meaning the n_max largest (by magnitude) will be labeled.

Usage

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

Arguments

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 earthquake data to be plotted. See the example for details.
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.
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.
...	other arguments passed on to layer. These are often aesthetics, used to set an aesthetic to a fixed value, like color = "red" or size = 3. They may also be parameters to the paired geom/stat.

Aesthetics

geom_timeline_label understands the following aesthetics (required aesthetics are in bold):

• x

• label

• n_max

Examples

## Not run: 
# You can plot a pair of earthquake timelines with labels as follows:

library(dplyr)

recent_earthquakes <- clean_earthquakes %>%
    filter(COUNTRY == "CHINA" | COUNTRY == "USA", DATE >= ymd('2000-01-01'))

g <- ggplot(recent_earthquakes,
            aes(x = DATE, y = COUNTRY, size = EQ_PRIMARY, color = TOTAL_DEATHS))
g <- g + geom_timeline(alpha = 0.5)
g <- g + geom_timeline_label(aes(label = LOCATION_NAME, n_max = 5))
g <- g + theme_classic()
g <- g + theme(legend.position = "bottom",
               axis.line.y = element_blank(),
               axis.ticks.y = element_blank(),
               axis.title.y = element_blank())
g <- g + guides(color = guide_colorbar(title = "# deaths"),
                size = guide_legend("Richter scale value"))
g

## End(Not run)

davidbody/earthquakes-package documentation built on May 14, 2019, 10:37 p.m.