Preprocessing

Once you have loaded your grades into a Gradebook, you might need to do some “preprocessing” to clean things up. For example, you may have given two different versions of each exam, represented by two different assignments in your grading platform that should be combined into one. gradelib provides functions for doing this kind of preprocessing in the gradelib.preprocessing module.

Combining assignment versions

Let’s say you gave three versions of an exam, which you named “Exam - Version A”, “Exam - Version B”, and “Exam - Version C”, along with a homework assignment named “Homework 1”:

>>> gradebook.assignments
Assignments(names=['Exam - Version A', 'Exam - Version B', 'Exam - Version C', 'Homework 1'])

Each student will have a grade for exactly one of the exam versions. You want to combine the three exam versions into one assignment, “Exam”, so that it contains the exam grade for each student. You can do this using the gradelib.preprocessing.combine_assignments() function, which takes in a gradebook and a dictionary mapping the new assignment name to a list of the old assignment names that should be combined:

>>> from gradelib.preprocessing import combine_assignment_versions
>>> combine_assignment_versions(gradebook, {
...      "Exam": ["Exam - Version A", "Exam - Version B", "Exam - Version C"]
... })
>>> gradebook.assignments
Assignments(names=['Exam', 'Homework 1'])

Like many functions in gradelib, this tries to be safe: if a student has a grade for more than one of the old assignments, it will raise an error. This is to prevent you from accidentally combining assignments that shouldn’t be combined.

Instead of typing out the list of old assignment names, you can use convenience methods on Gradebook.assignments to select them. For example, you can use gradelib.Assignments.starting_with():

>>> from gradelib.preprocessing import combine_assignment_versions
>>> combine_assignment_versions(gradebook, {
...      "Exam": gradebook.assignments.starting_with("Exam")
... })
>>> gradebook.assignments
Assignments(names=['Exam', 'Homework 1'])

Combining assignment parts

Sometimes an assignment will be split into multiple parts on your grading platform. For example, you might split your homework into “Homework 01 - Written Problems”, “Homework 01 - Programming Problem 01”, “Homework 01 - Programming Problem 02”, so that the students can submit each part separately (the programming problems each having their own autograder).

To combine these parts into a single assignment (by summing their points), you can use the gradelib.preprocessing.combine_assignment_parts() function.