Getting and Cleaning Data Course Project

The script run_analysis.R tidies data from the "Human Activity Recognition Using Smartphones" dataset found here: http://archive.ics.uci.edu/dataset/240/human+activity+recognition+using+smartphones

The data consists of sensor data (accelerometer and gyroscope) collected with an Samsung Smartphone. 30 volunteers participated, in the age bracket from 18 to 49. The data consists of different activities like walking, walking upstairs, sitting, laying etc. The dataset has been partitioned into 2 sets, 70% training data and 30% test data.

Used packages

To run the Script (run_analysis.R) you need the dplyr and tidyr packages (available on cran).

The tidy dataset is generated by running the following steps

• Creating the subdir "data", Downloading and unzipping the source data
• Reading the files for activities, features and the test/training data
• Combining the test and training data
• Renaming the columns by removing unnecessary dots
• Removing all columns that dont contain mean and std, while keep subject and activity
• Finally grouping subject and activity, summarizing by mean and writing the data to tidy.csv