In kaquilino/eqvis: Visualize Significant Earthquake Data

The eqvis package provides functions for cleaning and plotting the NOAA significant earthquake dataset using either a timeline or map. A sample of the NOAA data sample_eq is provided.

Clean Data

The earthquake data must be cleaned to utilize the timeline and map functions by using the eq_clean_data function. With this function, the country and colon are removed from the LOCATION_NAME and it is converted to title case. This provides for a better label. A DATE column is created from the date parts (YEAR, MONTH, DAY). The LATITUDE and LONGITUDE columns are converted to numerics.

This example demonstrates the use of eq_clean_data showing the before and after values. Notice the difference in values for the location name and the added DATE.

library(eqvis)
sample3 <- head(sample_eq[,c("YEAR","MONTH","DAY","LOCATION_NAME","LATITUDE","LONGITUDE")],3)
print.data.frame(sample3,row.names=FALSE)
print.data.frame(eq_clean_data(sample3),row.names=FALSE)

Timeline Info

A timeline can be produced using ggplot2 with the geom_timeline/stat_timeline functions. It will plot a timeline with points for each earthquake and can optionally include a size and color/fill aesthectics. If xmin and xmax aesthetics are provided, stat_timeline will subset the data. The geom_timeline_label function can be used to add a label geom. It wil print the label aesthetic for the top n_max earthquakes in terms of magnitude.

This example demonstrates the use of eq_clean_data, geom_timeline, and geom_timeline_label.

library(ggplot2)
library(scales)
library(eqvis)

ggplot(data=subset(eq_clean_data(sample_eq), !is.na(EQ_PRIMARY) & COUNTRY %in% c("USA")), 
       aes(x = DATE,
           y = COUNTRY,
           size = EQ_PRIMARY,
           xmin = as.Date('2012-01-01',"%Y-%m-%d"), 
           xmax = as.Date('2016-12-31',"%Y-%m-%d"),
           color = DEATHS, 
           fill = DEATHS,
           label = LOCATION_NAME)) +
    geom_timeline(alpha = .5) +
    scale_size_continuous(name = "Richter Scale Value") +
    scale_color_continuous(name = "# Deaths") +
    scale_fill_continuous(guide=FALSE) +
    labs(x = "DATE", y = "") +
    geom_timeline_label(aes(n_max = 3)) +
    theme(legend.position = "bottom",
          legend.key = element_blank(),
          legend.box = "horizontal",
          panel.background = element_blank(), 
          axis.line.x = element_line(size = 1, color = "black"), 
          axis.ticks.x = element_line(size = 1)) 

Map Info

A map can be produced using eq_map(). It will display circle markers at the lat/lon locations with a radius based on the magnitude of the earthquake and popup text reflecting the annotation column provided. An optional eq_create_label function is provided that will generate label text popup_text using the location name, magnitude and deaths for the earthquake.

This example demonstrates the use of eq_clean_data, eq_create_label, and eq_map.

library(eqvis)
library(leaflet)
library(magrittr)
library(dplyr)
library(lubridate)

sample_eq %>% 
eq_clean_data() %>% 
dplyr::filter(COUNTRY == "MEXICO" & lubridate::year(DATE) >= 2000) %>% 
dplyr::mutate(popup_text = eq_create_label(.)) %>% 
eq_map(annot_col = "popup_text")

Data

A sample_eq dataset is provided. It is a subset of the complete NOAA dataset, filtered for COUNTRY values USA and MEXICO and YEAR 2000-2017. It has the following structure:

str(sample_eq)

The complete NOAA earthquake dataset can be accessed from: https://www.ngdc.noaa.gov/nndc/struts/results?type_0=Exact&query_0=$ID&t=101650&s=13&d=189&dfn=signif.txt. It contains information about 5,933 earthquakes around the world over an approximately 4,000 year time span.

Note: This package was developed to work with positive years (A.D.) only.

kaquilino/eqvis documentation built on May 17, 2019, 2:44 p.m.