I just recently started with Canvas because Uppsala University has decided to use it as its upcoming LMS platform after a failed attempt with another product. Therefore I had already spent some time with Blackboard and was quite fond of the calculated questions<\/em> type in quizzes. I quickly found out that Canvas offers essentially the same functionality but a bit less comfortable.<\/p>\n A calculated question<\/em> or Formula Question <\/em>as it is called in the interface of Canvas is based on a table of pre-generated variable values and corresponding results. In the general case the variables are defined and the target function is entered using the web interface, then Canvas calculates random number values for the variables and the resulting answer value. However, as the designer you have no possibility to influence the variable values afterwards (unlike in Blackboard where you have a spreadsheet-like interface). Also, in Canvas, the equation cannot be altered once it has been entered – and the supported syntax is not very convenient for more complex problems. My hope was then for the API, since it seemed to support the creation of questions. But even though there is a Python library for the purpose of controlling Canvas, many of the functions are not very well documented. My first tries failed miserably but finally I was on the right track.<\/p>\n The cause of my problems was that the Canvas API uses different field identifiers and structures when creating a calculated question as when you retrieve the contents of an already existing question, as I of course did in my attempts to reverse-engineer the interface.<\/p>\n Here is now an example for a working solution to give you full control over the generation of Formula Qeustions using Python and the canvasapi <\/a>library. The example is in Python 3 and creates a question from the field of electronics – the voltage in a voltage divider. The Python script generates the variables, fills the variables with random numbers from a set of predefined, commonly used values. I tried to write the script more for readability than any pythonic optimization.Problem<\/h2>\n
\nI was also missing the ability to give a relative tolerance for the correct answers in a question, however, I found out that entering a percentage-sign exactly gives this behavior even though it does not seem documented anywhere.<\/p>\nSolution or problems?<\/h2>\n
Working solution<\/h2>\n
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