1Proj2Plot2.R

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# Author: Carolyn Clayton
# Date: 2015/01/08
# This is the import file for Course Project 1 for Exploratory Data Analysis
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# IMPORT AND FORMAT VARIABLES
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require(checkpoint)
checkpoint(snapshot = "2014-12-01", project = getwd(), verbose = T)
require(data.table)
data <- fread("household_power_consumption.txt", na.strings = c("?", "NA", ""), verbose = TRUE)
data$Date <- as.Date(data$Date, format = "%d/%m/%Y")
data <- data[data$Date >= "2007-02-01" & data$Date <= "2007-02-02"]
data$Global_active_power <- as.numeric(data$Global_active_power)
data$DateTime <- as.POSIXct(paste(as.character(data$Date),as.character(data$Time)))

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# PLOT 2
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with(data, plot(DateTime, Global_active_power, ylab = "Global Active Power (kilowatts)", xlab = "", type = "n"))
with(data, lines(DateTime, Global_active_power))
dev.copy(png, file = "plot2.png")
dev.off()