ExData_Plotting1/plot4.R at master · dzastera/ExData_Plotting1 · GitHub

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## Week 1, Course Project 1

# set working dir
setwd("~/R Projects/Coursera/04_ExpDataAnalysis/Week 1")

# load data
df <- read.table("household_power_consumption.txt", sep=";", header=TRUE, na.strings = "?")
df$DateTime <- strptime(paste(df$Date, df$Time), "%d/%m/%Y %T", tz="GMT")

# subset the data to 2007-02-01 to 2007-02-02
set <- subset(df, as.Date(DateTime)>="2007-02-01" & as.Date(DateTime)<="2007-02-02")


## Plot #4
# 2x2 plot

png("plot4.png",
    width = 480,
    height = 480,
    units = "px")

par(mfrow = c(2,2))

#plot 1
plot(x = set$DateTime,
     y = set$Global_active_power,
     type="l",
     xlab="",
     ylab="Global Active Power (kilowatts)")

#plot 2
plot(x = set$DateTime,
     y = set$Voltage,
     type = "l",
     xlab="datetime",
     ylab="Voltage")

#plot 3
plot(x = set$DateTime,
     y = set$Sub_metering_1,
     type="l",
     xlab="",
     ylab="Energy sub metering")

points(x = set$DateTime,
       y = set$Sub_metering_2,
       type = "l",
       col = "red")

points(x = set$DateTime,
       y = set$Sub_metering_3,
       type = "l",
       col = "blue")

legend("topright",
       legend = c("Sub_metering_1", "Sub_metering_2", "Sub_metering_3"),
       lty = "solid",
       col=c("black","red","blue"),
       bty="n")

#plot 4
plot(x = set$DateTime,
     y = set$Global_reactive_power,
     type = "l",
     xlab="datetime",
     ylab="Global_reactive_power")

dev.off()