geom_timeline_label: Annotations to the earthquake data

In Valentin-Konoshenko/Earthquakes4Coursera: Visualization of the earthquakes from the NOAA database

Description

This geom adds a vertical line to each data point with a text annotation (e.g. the location of the earthquake) attached to each line. There is an option to subset to n_max number of earthquakes, where we take the n_max largest (by magnitude) earthquakes. Aesthetics are x, which is the date of the earthquake and label which takes the column name from which annotations will be obtained. If n_max is omitted, each earthquake is annotated

Usage

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

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 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.
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.
n_max	A number of largest (by magnitude) earthquakes to be annotated. If omitted, each earthquake is annotated
...	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

library(dplyr)
library(ggplot2)
#without stratification with 2 greatest earthquakes are annotated
file_read() %>%
  eq_clean_data() %>%
  dplyr::filter(COUNTRY %in% c("USA", "CHINA"),
                between(lubridate::year(DATE), 2010, 2011)) %>%
  ggplot(aes(x = DATE,
             color = DEATHS,
             size = EQ_PRIMARY)) +
  geom_timeline(alpha = 0.4) +
  theme_timeline() +
  labs(size = "Richter scale value", colour = "# deaths") +
  geom_timeline_label(aes(label = LOCATION_NAME), n_max = 2)

Valentin-Konoshenko/Earthquakes4Coursera documentation built on May 23, 2019, 1:08 p.m.