gettingandcleaningdata

Coursera Getting And Cleaning Data Course

Course Project

Data

The data for this project can be found here: http://archive.ics.uci.edu/ml/datasets/Human+Activity+Recognition+Using+Smartphones

run_analysis.R

Process

1. Set the wd

   Set the wd to the same folder containing the run_analysis.R script.

2. Read in the training and test data

   • Reads the train data in
   • Binds the train data together (data frame: t)
   • Reads the test data in
   • Binds the test data together (data frame: v)
   • Binds the train and test data together (data frame: alldata)

3. Names the columns using the features.txt file

4. Subsets the alldata data frame to only mean and sd measurements (data frame: allmeansd)

5. Changes the Activity column to a factor and applies the descriptive names to Activity

6. Summarizes the data by aggregating the measurements by Subject + Activity groups (data frame: df)

7. Writes out the data frame df

8. The last line of code is how to read back in the output file into R