PavanKB/getdata-004-project

Getting and Cleaning Data Project

Introduction

This repo has been created for the Coursera course - Getting and Cleaning Data. The contents are :

1. run_analysis.R
2. summaryData.csv
3. completeData.csv
4. CodeBook for completeData.csv
5. README.md

The R file run_analysis.R contains the function run_analysis() that will analyse the data from Samsung Galaxy S2 during activities. This data was sourced from :

[1] Davide Anguita, Alessandro Ghio, Luca Oneto, Xavier Parra and Jorge L. Reyes-Ortiz. Human Activity Recognition on Smartphones using a Multiclass Hardware-Friendly Support Vector Machine. International Workshop of Ambient Assisted Living (IWAAL 2012). Vitoria-Gasteiz, Spain. Dec 2012

The function will process the training and testing data and combine them generating a data set(completeData.csv) containng the means and std of various measurements.

Another data set (summaryData.csv) is also created that contains the averages, grouped by Subject and Activity.

The data from folder test/Inertial Signals and train/Inertial Signals is not processed.

###How to Run :

1. Download the zip file form link
2. Unzip the contents into the working directory of you current R session. The folder structutre will be as shown:

<Working Directory>
	|-UCI HAR Dataset
        |-test
            +-Inertial Signals
            .-subject_test.txt
            .-X_test.txt
            .-y_test.txt
        |-train
            +-Inertial Signals
            .-subject_train.txt
            .-X_train.txt
            .-y_train.txt
        .-activity_labels.txt
        .-features.txt
        .-features_info.txt
        .-README.txt

3. Copy the run_analysis.R file from repo to the working directory.
4. Execute the following code:

> source('<Working Directory>/run_analysis.R')
> run_analysis()

5. The function will print the progress statements.

[1] "Read features.txt ."
[1] "Read X_train.txt ."
[1] "Read y_train.txt ."
[1] "Read subject_train.txt ."
[1] "Read X_test.txt ."
[1] "Read y_test.txt ."
[1] "Read subject_test.txt ."
[1] "Combined test and training data ."
[1] "Created filtered data with means and std."
[1] "Created summary data ."
[1] "Generated completeData.csv with the means and std values ."
[1] "Generated summaryData.csv with averages of completeData grouped by Subject,Activity."
[1] "END."

6. Once completed, two new CSV file should be available in the working directory.

###Output: The function will generate two CSV files.

completeData.csv

summaryData.csv