The philosophy and the approach =============================== The `nbgrader` project evolved from my experiences as an instructor and a student. This `excerpt from David Marr's book `_, *Vision*, is one of the core readings of the class that inspired the creation of `nbgrader`. Dr. Marr was an originator of the field of computational neuroscience and has been extremely influential in the field of computational cognitive science as well. On behalf of the many individuals who contribute to `nbgrader`, I hope you find this project enhances your teaching and learning experiences. -- *Jess Hamrick*, UC Berkeley How to structure course files ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ For instructor ease of use and developer maintenance, nbgrader makes a few assumptions about how your assignment files are organized. By default, nbgrader assumes that your assignments will be organized with the following directory structure: :: {course_directory}/{nbgrader_step}/{student_id}/{assignment_id}/{notebook_id}.ipynb where: * ``course_directory`` variable is the root directory where you run the nbgrader commands. This means that you can place your class files directory wherever you want. However, this location can also be customized (see the :doc:`configuration options `) so that you can run the nbgrader commands from anywhere on your system, but still have them operate on the same directory. * ``nbgrader_step`` - Each subcommand of nbgrader (e.g. ``assign``, ``autograde``, etc.) has different input and output folders associated with it. These correspond to the ``nbgrader_step`` variable -- for example, the default input step directory for ``nbgrader autograde`` is "submitted", while the default output step directory is "autograded". * ``student_id`` corresponds to the unique ID of a student. * ``assignment_id`` corresponds to the unique name of an assignment. * ``notebook_id`` corresponds to the name of a notebook within an assignment (excluding the .ipynb extension). Example ------- Taking the autograde step as an example, when we run the command ``nbgrader autograde "Problem Set 1"``, nbgrader will look for all notebooks that match the following path: :: submitted/*/Problem Set 1/*.ipynb For each notebook that it finds, it will extract the ``student_id``, ``assignment_id``, and ``notebook_id`` according to the directory structure described above. It will then autograde the notebook, and save the autograded version to: :: autograded/{student_id}/Problem Set 1/{notebook_id}.ipynb where ``student_id`` and ``notebook_id`` were parsed from the input file path. Here is how a sample directory structure for the course named ``course101`` might look, where the users ``bitdiddle`` and ``hacker`` have submitted solutions to the assignment ``ps1``: :: course101/ ├── gradebook.db ├── nbgrader_config.py ├── source │ ├── header.ipynb │ └── ps1 │ ├── jupyter.png │ ├── problem1.ipynb │ └── problem2.ipynb ├── release │ └── ps1 │ ├── jupyter.png │ ├── problem1.ipynb │ └── problem2.ipynb ├── submitted │ ├── bitdiddle │ │ └── ps1 │ │ ├── jupyter.png │ │ ├── problem1.ipynb │ │ ├── problem2.ipynb │ │ └── timestamp.txt │ └── hacker │ └── ps1 │ ├── jupyter.png │ ├── problem1.ipynb │ ├── problem2.ipynb │ └── timestamp.txt ├── autograded/ └── feedback/ On the student side, the directory structure follows a similar structure: :: course101/ ├── ps1 │ ├── jupyter.png │ ├── problem1.ipynb │ ├── problem2.ipynb │ └── feedback │ ├── 2019-05-31-11-48-34 │ │ ├── problem1.html │ │ └── problem2.html │ └── 2019-05-30-19-23-45 │ ├── problem1.html │ └── problem2.html └── ps2 Database of assignments ~~~~~~~~~~~~~~~~~~~~~~~ Additionally, nbgrader needs access to a database to store information about the assignments. This database is, by default, a sqlite database that lives at ``{course_directory}/gradebook.db``, but you can also configure this to be any location of your choosing. You do not need to manually create this database yourself, as nbgrader will create it for you, but you probably want to prepopulate it with some information about assignment due dates and students (see :doc:`managing_the_database`). Additionally, nbgrader uses SQLAlchemy, so you should be able to also use MySQL or PostgreSQL backends as well (though in these cases, you *will* need to create the database ahead of time, as this is just how MySQL and PostgreSQL work). Configuration files ~~~~~~~~~~~~~~~~~~~ To customize nbgrader's behavior, you can set configuration options in the ``nbgrader_config.py`` file. In particular, if you are using nbgrader with :doc:`JupyterHub `, you must set the course id in the nbgrader configuration file. A basic nbgrader config file would live at ``{course_directory}/nbgrader_config.py`` and might look like: :: c = get_config() c.CourseDirectory.course_id = "course101" There are many additional options you can configure. See :doc:`/configuration/config_options` for a full list.