Exploratory Data Analysis Project 1

This assignment uses data from the UC Irvine Machine Learning Repository, a popular repository for machine learning datasets. In particular, we will be using the "Individual household electric power consumption Data Set" which I have made available on the course web site:

• Dataset: Electric power consumption [20Mb]

• Description: Measurements of electric power consumption in one household with a one-minute sampling rate over a period of almost 4 years. Different electrical quantities and some sub-metering values are available.

Plot 1

#Load package needed library(data.table)

#create variable with all data energy <- read.table("household_power_consumption.txt", header = TRUE, sep = ";", na.strings = "?")

#check to see what data looks like
head(energy)

#Create variable with subset of full data with specified dates main_energy <- subset(energy, Date %in% c("1/2/2007", "2/2/2007"))

#Check to see if it worked should start at 2007 head(main_energy)

#Begin creating image for plot png("plot1.png", width = 480, height = 480)

#Create Histogram hist(main_energy$Global_active_power, main = "Global Active Power", xlab = "Global Active Power (kilowatts)", ylab = "Frequency", col = "red")

dev.off()

Plot 1

Plot 2

#Load package needed library(data.table)

#Create variable with full data energy <- read.table("household_power_consumption.txt", header = TRUE, sep = ";", na.strings = "?", stringsAsFactors = FALSE)

#Create variable with subset of data with specified dates main_energy <- subset(energy, Date %in% c("1/2/2007", "2/2/2007"))

#Turning Date from char to obj and creating variable to hold Date and Time main_energy$Date <- as.Date(main_energy$Date, format = "%d/%m/%Y") dt <- paste(as.Date(main_energy$Date), main_energy$Time) main_energy$Dt <- as.POSIXct(dt)

#Creating image process png("plot2.png", width = 480, height = 480)

#Creating plot with(main_energy, {plot(main_energy$Global_active_power ~ main_energy$Dt, type = "l", xlab = "", ylab = "Global Active Power (kilowatts)", )})

dev.off()

Plot 2

Plot 3

#Load packages needed library(data.table)

#Create variable with full data energy <- read.table("household_power_consumption.txt", header = TRUE, sep = ";", na.strings = "?", stringsAsFactors = FALSE)

#Create variable with subset of data with specified dates main_energy <- subset(energy, Date %in% c("1/2/2007", "2/2/2007"))

#Turning Date and Time from char to obj and creating variable to hold both main_energy$Date <- as.Date(main_energy$Date, format = "%d/%m/%Y") dt <- paste(as.Date(main_energy$Date), main_energy$Time) main_energy$Dt <- as.POSIXct(dt)

#Create image of plot png("plot3.png", width = 480, height = 480)

#Create plot plot(main_energy$Sub_metering_1 ~ main_energy$Dt, type = "l", xlab = "", ylab = "Energy sub metering") lines(main_energy$Sub_metering_3 ~ main_energy$Dt, col = "blue") lines(main_energy$Sub_metering_2 ~ main_energy$Dt, col = "red")

#Create legend to specificy the topright corner legend("topright", col = c("black", "red", "blue"), lty = 1, c("Sub_metering_1", "Sub_metering_2", "Sub_metering_3"))

dev.off()

Plot 3

Plot 4

#Load package needed library(data.table)

#Create variable with full data energy <- read.table("household_power_consumption.txt", header = TRUE, sep = ";", na.strings = "?", stringsAsFactors = FALSE)

#Create variable with subset of data and dates specified main_energy <- subset(energy, Date %in% c("1/2/2007", "2/2/2007"))

#Turn Date and Time from char to obj and store into one variable main_energy$Date <- as.Date(main_energy$Date, format = "%d/%m/%Y") dt <- paste(as.Date(main_energy$Date), main_energy$Time) main_energy$Dt <- as.POSIXct(dt)

#Create image of plots png("plot4.png", width = 480, height = 480)

#State layout for page 2 x 2 in this case par(mfrow = c(2, 2))

#First plot with(main_energy, {plot(main_energy$Global_active_power ~ main_energy$Dt, type = "l", xlab = "", ylab = "Global Active Power (kilowatts)", )})

#Second Plot plot(main_energy$Voltage ~ main_energy$Dt, type = "l", xlab = "datetime", ylab = "Voltage")

#Third Plot plot(main_energy$Sub_metering_1 ~ main_energy$Dt, type = "l", xlab = "", ylab = "Energy sub metering") lines(main_energy$Sub_metering_3 ~ main_energy$Dt, col = "blue") lines(main_energy$Sub_metering_2 ~ main_energy$Dt, col = "red")

legend("topright", col = c("black", "red", "blue"), lty = 1, c("Sub_metering_1", "Sub_metering_2", "Sub_metering_3"))

#Fourth Plot plot(main_energy$Global_reactive_power ~ main_energy$Dt, type = "l", xlab = "datetime", ylab = "Global_reactive_power")

dev.off()

Plot 4