PM 2.5 Line Charts

Libraries

library(data.table)
library(zoo)
library(dygraphs)
library(lubridate)
# Set Timezone
Sys.setenv(TZ='Asia/Shanghai')

Read and Preprocess Data

Using data from KDD CUP of Fresh Air.

bj_aq <- rbindlist(lapply(Sys.glob("../data/bj_*_renamed_aq.csv", dirmark = FALSE), fread))
bj_station <- fread("../data/Beijing_AirQuality_Stations.csv")
# Dedup
bj_aq <- bj_aq[!duplicated(bj_aq, from_last=T)]
# Parse time
bj_aq[, time:=with_tz(ymd_hms(bj_aq[, time], tz="UTC"), tz="Asia/Shanghai")]
# Filling Gaps in Time
full_keys <- expand.grid(
    time=seq(ymd_hms("2017-01-01 16:00:00"), 
             ymd_hms("2018-03-30 16:00:00"), 
             by="1 hour"),
    station_id=unique(bj_aq[,station_id])
)
bj_aq_full <- merge(bj_aq, full_keys, by=c("time", "station_id"), all.y=T)
# Convert to Date
bj_aq_full[, date:=as.Date(time, tz="Asia/Shanghai")]

# Calculate Daily Statistics (clips max upper to 500)
quality <- bj_aq_full[, .(
    median=as.numeric(median(PM25_Concentration, na.rm=T)), 
    avg=mean(PM25_Concentration, na.rm=T),
    upper=pmin(500, quantile(PM25_Concentration, probs=0.95, na.rm=T)), 
    lower=quantile(PM25_Concentration, probs=0.05, na.rm=T)), 
by=.(station_id, date)] 

Aotizhongxin (Olympic Sports Centre)

AQI calculation references: 1. https://aqs.epa.gov/aqsweb/documents/codetables/aqi_breakpoints.html 2. http://aqicn.org/mask/

dygraph(
    quality[station_id=="aotizhongxin_aq", .(date, lower, avg, upper)], 
    main="Aotizhongxin Daily PM2.5 Concentration (Max clipped to 500)") %>% 
dyAxis("x", drawGrid=F) %>% dyAxis("y", drawGrid=F) %>%
dySeries(c("lower", "avg", "upper"), label="PM2.5") %>%
dyShading(0, 12, color="#ccff99", axis="y") %>%
dyLimit(0, "good", labelLoc="right", color="grey") %>%
dyLimit(12, "moderate", labelLoc="right", color="grey") %>%
dyLimit(35, "unhealthy for sensitive groups", labelLoc="right", color="grey") %>%
dyLimit(55, "unhealthy", labelLoc="right", color="grey") %>%    
dyLimit(150, "very unhealthy", labelLoc="right", color="grey") %>% 
dyLimit(250, "hazardous", labelLoc="right", color="grey") %>% 
dyShading(12, 35, color="#ffffcc", axis="y") %>%
dyShading(35, 55, color="#ffebcc", axis="y") %>%
dyShading(55, 150, color="#ffcccc", axis="y") %>%
dyShading(150, 250, color="#e6ccff", axis="y") %>%
dyShading(250, 500, color="#ffddcc", axis="y") %>%
dyOptions(colors = RColorBrewer::brewer.pal(3, "Set1")) %>%
dyRangeSelector(dateWindow=c(as.Date("2017-01-01"), max(quality$date))) %>% 
dyLegend(width = 200, show = "follow")

Tiantan (Temple of Heaven)

dygraph(
    quality[station_id=="tiantan_aq", .(date, lower, avg, upper)], 
    main="Tiantan Daily PM2.5 Concentration (Max clipped to 500)") %>% 
dyAxis("x", drawGrid=F) %>% dyAxis("y", drawGrid=F) %>%
dySeries(c("lower", "avg", "upper"), label="PM2.5") %>%
dyShading(0, 12, color="#ccff99", axis="y") %>%
dyLimit(0, "good", labelLoc="right", color="grey") %>%
dyLimit(12, "moderate", labelLoc="right", color="grey") %>%
dyLimit(35, "unhealthy for sensitive groups", labelLoc="right", color="grey") %>%
dyLimit(55, "unhealthy", labelLoc="right", color="grey") %>%    
dyLimit(150, "very unhealthy", labelLoc="right", color="grey") %>% 
dyLimit(250, "hazardous", labelLoc="right", color="grey") %>% 
dyShading(12, 35, color="#ffffcc", axis="y") %>%
dyShading(35, 55, color="#ffebcc", axis="y") %>%
dyShading(55, 150, color="#ffcccc", axis="y") %>%
dyShading(150, 250, color="#e6ccff", axis="y") %>%
dyShading(250, 500, color="#ffddcc", axis="y") %>%
dyOptions(colors = RColorBrewer::brewer.pal(3, "Set1")) %>%
dyRangeSelector(dateWindow=c(as.Date("2017-01-01"), max(quality$date))) %>% 
dyLegend(width = 200, show = "follow")

Miyun (A Suburban District)

dygraph(
    quality[station_id=="miyun_aq", .(date, lower, avg, upper)], 
    main="Miyun Daily PM2.5 Concentration (Max clipped to 500)") %>% 
dyAxis("x", drawGrid=F) %>% dyAxis("y", drawGrid=F) %>%
dySeries(c("lower", "avg", "upper"), label="PM2.5") %>%
dyShading(0, 12, color="#ccff99", axis="y") %>%
dyLimit(0, "good", labelLoc="right", color="grey") %>%
dyLimit(12, "moderate", labelLoc="right", color="grey") %>%
dyLimit(35, "unhealthy for sensitive groups", labelLoc="right", color="grey") %>%
dyLimit(55, "unhealthy", labelLoc="right", color="grey") %>%    
dyLimit(150, "very unhealthy", labelLoc="right", color="grey") %>% 
dyLimit(250, "hazardous", labelLoc="right", color="grey") %>% 
dyShading(12, 35, color="#ffffcc", axis="y") %>%
dyShading(35, 55, color="#ffebcc", axis="y") %>%
dyShading(55, 150, color="#ffcccc", axis="y") %>%
dyShading(150, 250, color="#e6ccff", axis="y") %>%
dyShading(250, 500, color="#ffddcc", axis="y") %>%
dyOptions(colors = RColorBrewer::brewer.pal(3, "Set1")) %>%
dyRangeSelector(dateWindow=c(as.Date("2017-01-01"), max(quality$date))) %>% 
dyLegend(width = 200, show = "follow")