Check your understanding of the previous reading: the commands for moving around a file system, absolute and relative paths, and why forward slashes suit Python.

Question 1

Write the command for moving up a directory.

Show worked solution

A pair of periods means the folder one level up, so the command is cd .. (cd ../ works too).

Question 2

Write the command for moving to a folder named "homework" that is in the current directory.

Show worked solution

The folder is in the current directory, so its relative path is simply its name: cd homework.

Question 3

Write the command for printing the current directory.

Show worked solution

PWD stands for Print Working Directory: pwd.

Question 4

Write the command for listing files in the current directory.

Show worked solution

ls stands for "list": it lists the files in the current working directory.

Question 5

Given the following map of a filesystem…

/root/
    python/
        readme.rst
        python.exe
        qt.conf
    classes/
        cs1064/
            adventure_game.py
            assignment2.txt
            ethics_submission.pdf
        dog1223/
            readings.pdf
            project1.docx
            DCIM-1221.jpg
    data/
        survey_results.csv
        state_names.json
        f15_student_logs.txt

Answer the following:

Question	Answer
What is the full path to the folder "data/"?
What is the full path to the file "DCIM-1221.jpg"?
If you are currently in directory `data/`, which of the following is NOT a path to the `readings.pdf` file?
If you are currently in directory `cs1064/`, which of the following is NOT a path to the `survey_results.csv` file?

Question 6

Why should you tend to use forward slashes in Python?

Select every answer that applies, then check.

Back slashes in string literals represent escape characters, which can mess up the path.
Correct. In a Python string, a backslash starts an escape sequence, so a path with single backslashes can turn into something else. That's why the reading says you would otherwise need to escape the backslashes with extra backslashes.
Back slashes are backwards, which means that only backwards people use them.
Not a reason. Backslashes are the usual separator on Windows; the trouble is how Python strings treat them.
Forward slashes look prettier to everyone.
Not a reason. How they look doesn't matter; what matters is that forward slashes need no escaping and work across platforms.
Forward slashes tend to work in both Mac and Windows.
Correct. The reading recommends forward slashes because they tend to work regardless of the platform.

Question 7

True or false: The pwd command works in every Python environment.

Select one answer, then check.

True
Not quite. pwd is a command for a command line; it's not actually a Python command, so a Python environment doesn't run it as Python code.
False
Correct. pwd belongs to the command line, not to Python: it's not actually a Python command.