tianwenlan / Getting_and_Cleaning_Data

Getting and Cleaning Data - Course Project

This is the course project for Getting and Cleaning Data on Coursera.

This repository contains follwoing files:

• README.md: provides an overview of the data set and how it was created.
• tidy_data.txt: final data set.
• CodeBook.md: describes the contents of the data set (data, variables and transformations used to generate the data).
• run_analysis.R: R script to create the yidy data set

run_analysis.R has following steps:

• Download and unzip the dataset
• Read the training and test datasets, and merge them to one dataset
• Extracts only the measurements on the mean and standard deviation for each measurement
• Read the activity and subject data for each dataset, and convert the activity and subject columns into factors
• Creates a tidy dataset TidyData.txt that consists of the mean value of each variable for each subject and activity.