YanQiWeek3CodingPractice

class_data <- c("numeric", "character", "factor", "numeric", "numeric")
pollution <- read.csv("avgpm25.csv", colClasses = class_data)
head(pollution)

##        pm25  fips region longitude latitude
## 1  9.771185 01003   east -87.74826 30.59278
## 2  9.993817 01027   east -85.84286 33.26581
## 3 10.688618 01033   east -87.72596 34.73148
## 4 11.337424 01049   east -85.79892 34.45913
## 5 12.119764 01055   east -86.03212 34.01860
## 6 10.827805 01069   east -85.35039 31.18973

str(pollution)

## 'data.frame':    576 obs. of  5 variables:
##  $ pm25     : num  9.77 9.99 10.69 11.34 12.12 ...
##  $ fips     : chr  "01003" "01027" "01033" "01049" ...
##  $ region   : Factor w/ 2 levels "east","west": 1 1 1 1 1 1 1 1 1 1 ...
##  $ longitude: num  -87.7 -85.8 -87.7 -85.8 -86 ...
##  $ latitude : num  30.6 33.3 34.7 34.5 34 ...

fivenum(pollution$pm25)

## [1]  3.382626  8.547590 10.046697 11.356829 18.440731

summary(pollution$pm25)

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   3.383   8.549  10.047   9.836  11.356  18.441

boxplot(pollution$pm25, col = "blue")

library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

filter(pollution, pm25 > 15)

##       pm25  fips region longitude latitude
## 1 16.19452 06019   west -119.9035 36.63837
## 2 15.80378 06029   west -118.6833 35.29602
## 3 18.44073 06031   west -119.8113 36.15514
## 4 16.66180 06037   west -118.2342 34.08851
## 5 15.01573 06047   west -120.6741 37.24578
## 6 17.42905 06065   west -116.8036 33.78331
## 7 16.25190 06099   west -120.9588 37.61380
## 8 16.18358 06107   west -119.1661 36.23465

library(maps)

## Warning: package 'maps' was built under R version 4.5.1

map("county", "california")
with(filter(pollution, pm25 > 15), points(longitude, latitude))

hist(pollution$pm25, col = "green")
rug(pollution$pm25)

hist(pollution$pm25, col = "green", breaks = 100)
rug(pollution$pm25)

boxplot(pollution$pm25, col = "blue")
abline(h = 12)

hist(pollution$pm25, col = "green")
abline(v = 12, lwd = 2)
abline(v = median(pollution$pm25), col = "magenta", lwd = 4)

library(dplyr)
table(pollution$region) %>% barplot(col = "wheat")

boxplot(pm25 ~ region, data = pollution, col = "red")

par(mfrow = c(2, 1), mar = c(4, 4, 2, 1))
hist(subset(pollution, region == "east")$pm25, col = "green")
hist(subset(pollution, region == "west")$pm25, col = "green")

with(pollution, plot(latitude, pm25))
abline(h = 12, lwd = 2, lty = 2)

with(pollution, plot(latitude, pm25, col = region))
abline(h = 12, lwd = 2, lty = 2)

levels(pollution$region)

## [1] "east" "west"

par(mfrow = c(1, 2), mar = c(5, 4, 2, 1))
with(subset(pollution, region == "west"), plot(latitude, pm25, main = "West"))
with(subset(pollution, region == "east"), plot(latitude, pm25, main = "East"))

library(lattice)
xyplot(pm25 ~ latitude | region, data = pollution)

library(ggplot2)
qplot(latitude, pm25, data = pollution, facets = . ~ region)

## Warning: `qplot()` was deprecated in ggplot2 3.4.0.
## This warning is displayed once every 8 hours.
## Call `lifecycle::last_lifecycle_warnings()` to see where this warning was
## generated.