CS 61A uses a program called
ok to test and submit homework
assignments, labs, and projects.
Every programming assignment will include a
.zip archive that
contains the following:
- Starter code
- A copy of
After extracting the contents of the archive, you can begin your assignment.
Signing in with Ok
To get started, open your terminal, and
cd into the right directory
(you should see a file called
ok when you
ls in the right
Try the following command:
This runs the tests (don't worry if the tests fail at first; you haven't written code yet!).
The first time you run
ok, you will be asked for your bCourses email.
This should be your Berkeley email address (ending with
If you have more than one, please use the one that you log into your
bConnected Google account with.
If you don't have a Berkeley email address, you can create one here by logging in to your CalNet account.
After typing in your email, your web browser will open an
authentication page. Click "Accept" to authenticate
If you see an error message that indicates you are not enrolled in the course, make sure you are using the email address that would appear on the course roster. If the email you used is correct, you may continue to use the email; your submissions will still be saved. You must contact your TA for that email address to be enrolled.
If you typed your email incorrectly, you can re-authenticate with the following command:
python3 ok --authenticate
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Make sure you have the 64-bit version of Python 3 installed. You can check whether you have the incorrect 32-bit version by running the following command in your terminal.
python3 -c "import struct,platform;print(8 * struct.calcsize('P'), platform.python_version())"
Double check your internet connection. If you're on campus, try using AirBears2.
Testing with Ok
After writing some code, you can test your code with
ok in various
Test specific questions
To test a specific question, use the
-q option with the name of the question:
python3 ok -q <question>
Test all questions
You can run all the tests with the following command:
Display all tests
By default, only tests that fail will appear. If you want to see how you did
on all tests, you can use the
python3 ok -v
If you do not want to send your progress to our server or you have any problems
logging in, add the
--local flag to block all communication:
python3 ok --local
Adding your own tests
You can write your own tests and run them using
ok. By default, a test file
will be named
mytests.rst. You may use a different name, but you will need to
specify it when running tests.
Running your own tests
To run all your tests in
mytests.rst with verbose results:
python3 ok -t -v
If you put your tests in a different file or split your tests up into multiple files:
python3 ok -t your_new_filename.rst
To run just the tests from suite 1 case 1 in
python3 ok -t --suite 1 --case 1
You might have noticed that there's a "test coverage" percentage for your tests (note that coverage statistics are only returned when running all tests). This is a measure of your test's code coverage.
To receive guidance on which lines you should test to increase your coverage:
python3 ok -t -cov
Code coverage won't include
ok tests, so the coverage percentage might be
higher in reality.
While code coverage is a useful tool, you should not get fixated on this number. It is better to write tests that help you complete the problem and make life easier instead of achieving a higher coverage.
When you are ready to submit, run
ok with the
python3 ok --submit
ok will display a submission URL, with which you can view
your submission on okpy.org.
You can go to okpy.org to check your submissions and backups. Make sure you sign in with the same bCourses email that you authenticated with.