Demos

A demo of the matrix entry part and its options.

A few questions which show off the new matrix entry part.

Demonstrates how to display a plot generated in R.

Some questions to show off features of Numbas, linked from the Numbas homepage.

Given the gradient of a slope and the coefficient of friction for a mass resting on it, use the equations of motion to calculate how it moves.

Includes a GeoGebra rendering of the model.

A demo of the number entry part and its options.

The student is shown a plot of a mystery function. They can enter values of $x$ check, within the bounds of the plot.

They're asked to give the formula for the function, and then asked for its value at a very large value of $x$.

A plot of the student's function updates automatically as they type. Adaptive marking is used for the final part to award credit if the student gives the right value for their incorrect function.

Examples of the following custom part types: Yes/no, List of numbers, Give a numerical input for an expression, Number entry modulo.

This shows how to take an expression given by the student and plot the implicit curve of points where it equals zero.

Some questions which use JSXGraph to create interactive graphics.

This question shows a JSXGraph diagram above a mathematical expression input, containing a plot of the expression the student enters.

In the first part, the student must write an R function to compute the first $n$ terms of the series $\frac{1}{k!}$.

In the second part, they must use that function to calculate an approximation to $e$ using a given number of terms of the series.

Several questions on interrogating the mtcars dataset built in to R.

The student must write R code to assign the given value to the variable x.

This question shows how to display a plot generated in matplotlib from code written by the student.

Given an unknown list, the student must write Python code to create a copy of it.

There's an alternative to catch the case where the student's variable is just a reference to the original list.

Given an unknown list, the student has to write code to return the last item in the list.

Given a randomly-generated list, the student must write code to return its first value.

There's an alternative to check if they get the second item, which they might do if they don't realise Python lists are zero-indexed.

The student must write code to compute the standard deviation of an unknown list of measurements.

The suggested answer uses numpy.std.

This is the simplest demonstration of the "code" part type I could think of: write Python to assign x = 1.

An alternative answer gives a hint if the student's code doesn't define x at all.

A demonstration of embedding various kinds of media in a question.

This question demonstrates how to use GeoGebra applets in explore mode.

The student must construct a polygon by adding points one at a time. At any point, they can answer the question, "Is the centroid inside the polygon?"

GeoGebra's IsInRegion command is used to decide if the centroid is inside the polygon.

This exam collects some questions demonstrating different uses of the programming extension and the Code part type, to mark code written in Python and R.

The student is asked to integrate a given function. The marking algorithm differentiates the student's answer, and checks that it is equivalent to the original function.

This question demonstrates how to construct a JSXGraph diagram using JessieCode.

The construction shows a triangle and its orthocentre, circumcentre and centroid. They are always collinear. You can move the vertices of the triangle.

A demo of the main new features in Numbas v5: explore mode, alternative answers and "Choose from a menu" question navigation.

All the answers in this question are equations. In order to mark each equation, Numbas needs to pick some values that satisfy the equation and some that don't, and check that the student's answer agrees with the expected answer.

Any equation with the same solution set as the expected answer will be marked correct.

A demo of how custom marking algorithms can be used to replace the built-in marking methods.

This question demonstrates a few ways of interacting with a Venn diagram drawn using JSXGraph.