getdata-005-assignment

Following repository contains the solution for the assignment from "Getting and Cleaning data" course.

Content of the repository

1. Readme.md - this file, describing the repository
2. run_analysis.R - script performing the analysis on the data set
3. CodeBook.md - file describing the content of run_analysis.md output

Requirements

• R
• Script and data in the same directory
• Data stored in "data" directory

Data Source

Human Activity Recognition Using Smartphones Data Set http://archive.ics.uci.edu/ml/datasets/Human+Activity+Recognition+Using+Smartphones

Following files have been used in analysis:

• activity_labels.txt
• features.txt
• test/X_test.txt
• test/y_test.txt
• test/subject_test.txt
• train/X_train.txt
• train/y_train.txt
• train/subject_train.txt

Output

run_analysis.R generates:

• data frame "data" (data set as stated in assignment specification) - merged data source
• data frame "summary" (tidy data set as stated in assignment specification) - summarized data
• file "data.csv" - CSV with the content of data frame "data"
• file "summary.csv" - CSV with the content of data frame "summary"

Measurements transformation

Original measurements (featuers) labels where transformed for better readibility:

• CamelCase has been applied
• Prefixes t and f where replaced by Time and Freq (for Frequency)
• Special characters removed
• Duplicates removed (i.e. BodyBody)
• Acc replaced to Accel (for Accelerometer)

Activities transformation

Activity labels were transformed from upper case to lower case words starting with a uppercase letter.

Behind the scenes

Please refer to the script's comments which describe what is happening.