plot4.R

dset<-read.table("household_power_consumption.txt", header=TRUE, sep=";",na.strings="?")
dset$Date<-as.Date(dset$Date, format="%d/%m/%Y")
dataToUse <- dset[dset$Date >= "2007-02-01" & dset$Date <= "2007-02-02", ]
dataToUse$dtime <- paste(dataToUse$Date, dataToUse$Time)
dataToUse$dtime <- strptime(dataToUse$dtime, format="%Y-%m-%d %T")
png(filename = "plot4.png", width = 480, height = 480, units = "px")
par(mfcol=c(2,2))
with(dataToUse,plot(dtime,Global_active_power, type="l",ylab="Global Active Power",xlab=""))
with(dataToUse,plot(dtime,Sub_metering_1, type="l",xlab="",ylab="Energy sub metering"))
with(dataToUse,lines(dtime,Sub_metering_2, col="red"))
with(dataToUse,lines(dtime,Sub_metering_3, col="blue"))
legend("topright", legend=c("Sub_metering_1","Sub_metering_2","Sub_metering_3"),pch=151, col=c("black","red","blue"), bty="n")
with(dataToUse,plot(dtime,Voltage, type="l",xlab="datetime"))
with(dataToUse,plot(dtime, Global_reactive_power, type="l",xlab="datetime"))
dev.off()