Following are steps are performed in sequence to load and transform the raw data obtained to prepare the tidy.txt file -

1 Loading the train CSV files data into Train_data table

2 Loading the test CSV file data into Test_data table

3 Loading the activity labels csv file into activityLabels_data table

4 Loading the features into features table and make the feature names better suited for R with some substitutions

5 Renaming feature data to have meaningful column names

6 Loading train and test data into one consolidated full_data table

7 Capturing Mean and Standard deviation

8 Updating Features table with Mean and Standard Deviation

9 Appending Subject and Activity columns

10 Trimming table to have just key columns

11 Updating full_data table with the features

12 Putting a loop to load full_data table with updates features and activity

13 Initial Loading of tidy table with raw data

14 Refining tidy table by removing unwanted subject and activity columns

15 checking dimensions of tidy

16 Writing tidy table contents onto tidy.txt