plot4.R

## Loading the dplyr library
library(dplyr)
## Loading the file
household <- read.csv("household_power_consumption.txt", header=TRUE, sep=";")
## Select only the dates we are interested in
householdSub <- filter(household, Date=="1/2/2007" | Date=="2/2/2007")
## Formatting the dates
householdSub <- mutate(householdSub, DateTime =  as.POSIXct(paste(Date, Time), format = '%d/%m/%Y %H:%M:%S'))
## Converting the factors as numerics
householdSub <- mutate(householdSub, Global_active_power = as.numeric(as.character(householdSub$Global_active_power)))
householdSub <- mutate(householdSub, Sub_metering_1 = as.numeric(as.character(householdSub$Sub_metering_1)))
householdSub <- mutate(householdSub, Sub_metering_2 = as.numeric(as.character(householdSub$Sub_metering_2)))
householdSub <- mutate(householdSub, Sub_metering_3 = as.numeric(as.character(householdSub$Sub_metering_3)))
householdSub <- mutate(householdSub, Voltage = as.numeric(as.character(householdSub$Voltage)))
householdSub <- mutate(householdSub, Global_reactive_power = as.numeric(as.character(householdSub$Global_reactive_power)))
## Create the file to draw in
png(file = "plot4.png", width = 480, height = 480)
## Define 2 plots per row / 2 plots per col
par("mfcol"= c(2,2))
## Setting the background color as transparent
par("bg"= "transparent")
## Drawing the plot1
with(householdSub, plot(DateTime, Global_active_power, type="l", xlab="", ylab="Global Active Power (kilowatts)"))
## Drawing the plot2
with(householdSub, plot(DateTime, Sub_metering_1, type="l", xlab="", ylab="Energy sub metering", bg="transparent"))
with(householdSub, (lines(DateTime, Sub_metering_2, col="red")))
with(householdSub, (lines(DateTime, Sub_metering_3, col="blue")))
legend("topright", bty="n", lty=1, col=c("black","red","blue"), legend=c("Sub_metering_1","Sub_metering_2","Sub_metering_3"))
## Drawing the plot3
with(householdSub, plot(DateTime, Voltage, type="l", xlab="datetime", bg="transparent"))
## Drawing the plot4
with(householdSub, plot(DateTime, Global_reactive_power, type="l", xlab="datetime", bg="transparent"))
## Closing the device
dev.off()