Leaflet Assignment

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Step 1: Load the dataset from a previous analysis using the NOAA data [weather events database]. For details of how the dataset was created click here.

strm2b <- read.csv("~/storm_refined.csv")

Step 2: Load libraries that will be needed for this assignment.

## load libraries
library(dplyr)
library(leaflet)

Step 3: Prep dataset by selecting weather events in Texas that caused some level of health (fatality/injury) or economic damage (crop/property damage).

## limit NOAA storm dataset (from Reproducible Research) to 1994 and later, eliminate empty lat/long, and add decimal to lat/long
storm <- strm2b %>%
  filter(byear >= 1994 & LATITUDE != 0) %>%
  mutate(lat = paste(substr(LATITUDE, 1, 2), ".", substr(LATITUDE, 3, length(LATITUDE)), sep = ""), 
         lng = paste(substr(LONGITUDE, 1, 2), ".", substr(LONGITUDE, 3, length(LONGITUDE)), sep = ""),
         color = ifelse(evtCat == "wind_land", "orange", 
                 ifelse(evtCat == "wind_water", "green",
                 ifelse(evtCat == "water", "blue",
                 ifelse(evtCat == "heat", "maroon",
                 ifelse(evtCat == "cold", "pink", "black")))))) %>%
  mutate(lat = as.numeric(lat), lng = as.numeric(lng), long = -lng) %>%
  select(byear, EVTYPE, evtCat, FATALITIES, INJURIES, STATE, cropDmg, propDmg, lat, long, color)

## limit dataset to Texas events with valid longitude
storm_tx <- storm %>%
  filter(STATE == "TX" & long < -50.00)

## limit Texas data to those with health or economic damage
storm_dmg_tx <- storm_tx %>%
  filter(FATALITIES > 0 | INJURIES > 0 | cropDmg > 0 | propDmg > 0)

Step 4: Create map of Texas weather events and center around San Antonio.

library(leaflet)
strm_txmap <- storm_dmg_tx %>%
  leaflet() %>%
  addTiles() %>%
  setView(-98.4936, 29.4241, zoom = 10) %>%
  addCircleMarkers(lat = storm_dmg_tx$lat, 
             lng = storm_dmg_tx$long, 
             popup = paste("<b>Year:</b>", storm_dmg_tx$byear, "<br>",
                           "<b>Lat / Long:</b>", storm_dmg_tx$lat, storm_dmg_tx$long, "<br>",
                           "<b>Weather Event Type:</b>", storm_dmg_tx$EVTYPE, "<br>", 
                           "<b>Weather Category:</b>", storm_dmg_tx$evtCat, "<br>",
                           "<b>Fatalities:</b>", storm_dmg_tx$FATALITIES, "<br>",
                           "<b>Injuries:</b>", storm_dmg_tx$INJURIES, "<br>",
                           "<b>Crop Damage (Thousands):</b>", storm_dmg_tx$cropDmg, "<br>",
                           "<b>Property Damgage (Thousands)</b>:", storm_dmg_tx$propDmg, "<br>"),
             color = storm_dmg_tx$color, 
             fillColor = storm_dmg_tx$color) %>%
  addLegend(position = "topleft", 
            title = "Weather Events Legend",
            labels = c("wind_land", "wind_water", "water", "heat", "cold", "other"), 
            colors = c("orange", "green", "blue", "maroon", "pink", "black"))
strm_txmap