README.md

In Solymi90/r.prog.capstone: Capstone Project of Mastering Software Development in R on Coursera

Mastering Software Development in R

Capstone Project - NOAA Earthquake Visualizations

Created by: Gábor Solymosi

This is an R package created for the purpose of visualizing NOAA earthquake data. It processes data from NOAA database.

Description

The package includes several exported functions to handle NOAA data. The provided data set includes data on earthquakes starting year 2150 B.C. and contains dates, locations, magnitudes, severity and other features.

This package handles basic data cleaning using function eq_clean_data() and then two types of visualizations. The first is a ggplot2-based earthquake timeline of selected earthquakes using geom_timeline() and geom_timeline_label() with optional usage of theme_timeline() function. The second visualization is based on leaflet package and shows the earthquakes with some basic parameters on a map.

```{r, echo = FALSE, include = FALSE} library(r.prog.capstone) library(dplyr) library(ggplot2) library(readr) library(grid) library(lubridate) library(leaflet) library(scales)

The readme file gives a brief overview of the `r.prog.capstone` R package created for the purpose of visualizing NOAA earthquake data. It processes data from [NOAA database](https://www.ngdc.noaa.gov/nndc/struts/form?t=101650&s=1&d=1) and visualizes them using `ggplot2` and `leaflet` packages. 

## Installation

To install the package type the following (the development version from Github):

library(devtools) install_github("Solymi90/r.prog.capstone") library(r.prog.capstone)

## Package functions

There are six exported functions available to users:

- `eq_clean_data()`
- `geom_timeline()`
- `geom_timeline_label()`
- `theme_timeline()`
- `eq_create_label()`
- `eq_map()`

Please find a short description with examples on how to use the functions. The example data from NOAA can be found in the package directory under `\extdata` folder.

## Clean data

The first function is required to clean data for the visualization. It creates a DATE column in `Date` format, transforms latitude and longitude to numeric format and trims country from LOCATION_NAME.

```{r eq_read_example, message = FALSE}
file_name <- system.file("extdata/data.gz", package = "r.prog.capstone")
data <- readr::read_delim(file_name, delim = "\t")

eq_clean_data(data)

Visualize earthquake timeline

The next three functions utilize ggplot2 package to visualize earthquake timeline. The basic geom_timeline() geom requires clean data from the previous paragraph. The required aesthetics is x with dates, optional are y for grouping by country, and size and color that can be use according to user needs. The geom_timeline_label() function requires additional label aesthetic for labeling. For better visualization of these two geoms, theme_timeline() theme was added. Here is an example:

```{r eq_timeline_example, fig.width = 7, fig.height = 4} data %>% eq_clean_data() %>% filter(COUNTRY %in% c("GREECE", "ITALY"), YEAR > 2000) %>% ggplot(aes(x = DATE, y = COUNTRY, color = as.numeric(TOTAL_DEATHS), size = as.numeric(EQ_PRIMARY) )) + geom_timeline() + geom_timeline_label(aes(label = LOCATION_NAME), n_max = 5) + theme_timeline() + labs(size = "Richter scale value", color = "# deaths")

## Visualize earthquakes on map

The package utilized `leaflet` functions to visualize earthquakes on a map using `eq_map()` function. The map is automatically trimmed to display the input data frame. Optional annotations can be created using `eq_create_label()` function. The result is an interactive map where user can click on individual points to get details:

```{r eq_map_example, fig.width = 7, fig.height = 4}
data %>% 
  eq_clean_data() %>% 
  dplyr::filter(COUNTRY == "MEXICO" & lubridate::year(DATE) >= 2000) %>% 
  dplyr::mutate(popup_text = eq_create_label(.)) %>% 
  eq_map(annot_col = "popup_text")

Solymi90/r.prog.capstone documentation built on May 27, 2019, 7:42 a.m.