Sum of triangular numbers (with optional steps)

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Christian Lawson-Perfect 1 year, 10 months ago

Published this.

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Christian Lawson-Perfect commented 3 years, 1 month ago

I've fixed the expected answer display.

You need to be careful when testing numpy arrays. When a and b are arrays, a == b returns an array, not a bool.

So, to test if two arrays are equal, you need np.array_equal(a,b).

Also, Pyodide doesn't seem to be able to post numpy values back from the worker, so you need to return a Python built-in type. I've added a special case checking for the numpy.bool_ type, because wrapping every test in bool() would get boring quickly, but you can't pass back numpy.array or numpy.int64/float64.

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George Stagg commented 3 years, 1 month ago

Apologies, some of those issues might be me, I'm adding back R into the latest version of the extension.

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Chris Graham commented 3 years, 1 month ago

Couple of things to look at in the programming extension when I tried this out:

Noticed an issue in the marking of the steps:

"Failed to execute 'postMessage' on 'DedicatedWorkerGlobalScope': [object Object] could not be cloned."

The correct answer is actually the placeholder content I think?

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Chris Graham 3 years, 1 month ago

Created this.

There is only one version of this question that you have access to.

Question statement

Give any introductory information the student needs.

			Name	Type	Generated Value

nmax

integer

100

Automatically regenerate variables?

Name

Data type

Value

xxxxxxxxxx
 
random(100..250#50)

JME function reference

Description

The number of triangular numbers to sum

Describe what this variable represents, and list any assumptions made about its value.

Can an exam override the value of this variable?

Generated value: `integer`

100

This variable doesn't seem to be used anywhere.

Parts

Code

Code

Ask the student a question, and give any hints about how they should answer this part.

Set a variable s to the sum of the first {nmax} triangular numbers,

$s = \sum_{n=1}^{\var{nmax}}\frac{n(n+1)}{2}$

Help with this part type

Marks

Penalty for revealing steps

Show correct answer on reveal?

Show score feedback icon?

Show the input hint?

Code language

The language that the student's code will be written in.

Correct answer

xxxxxxxxxx
 
import numpy as np
n = np.arange(1,101)
t = n*(n+1)/2
s = sum(t)

A correct answer to the part.

Substitute question variables into the correct answer?

If ticked, then JME expressions between curly braces will be evaluated and substituted into the correct answer.

If not ticked, then the correct answer will be displayed exactly as it is.

Show stdout?

If ticked, the STDOUT produced after running the student's code will be shown in the feedback.

Show stderr?

If ticked, the STDERR produced after running the student's code will be shown in the feedback.

Show errors produced by marking tests?

Placeholder

xxxxxxxxxx
 
import numpy as np
​
# Complete the code to find s
​
s = 

Initial text for the code editor

Student code modifier

​

JME expression to modify the student's submitted code before being passed to the marking template. The student's code is available as the string variable studentAnswer.

Preamble

​

This code is run before the student's code. Define anything that the student's code or your tests need.

Postamble

xxxxxxxxxx
 
print(type(s))

This code is run after the student's code but before the validation and unit tests.

Format postamble output as code?

If ticked, any output produced by the postamble will be formatted in monospace font, with whitespace preserved. If not ticked, it'll be presented as prose text or HTML.

Marking tests

xxxxxxxxxx
 
[
  ["Correct s", 1, "(sum(np.arange(1,nmax+1)*(np.arange(1,nmax+1)+1)/2) == s).all()"]
]

A list of tests used to mark the student's answer.
Each item is a list with three values:

The name of the test, shown to the student above any feedback.
The proportion of the credit available for the part to award if this test is passed.
The code to run.

Validation tests

xxxxxxxxxx
 
[
  py_valid_defined('s'),
]

A list of tests used to validate that the student's code is acceptable.
Each item is a list with two string values:

A name which will be shown to the student if the test fails.
The code to run.

Variables to include in code

xxxxxxxxxx
 
dict("nmax":nmax)

Give a dictionary mapping variable names to their values. These variables will be available in the code that is run.

Advice

{code_block("import numpy as np\nn = np.arange(1,101)\nt = n*(n+1)/2\ns = sum(t)",["language":"python"])}

Give a worked solution to the whole question.

Use this tab to check that this question works as expected.

There was an error which means the tests can't run:

Part	Test	Passed?
Code
Code		Hasn't run yet
Code
Code		Hasn't run yet
Code
Code		Hasn't run yet
Code
Code		Hasn't run yet

This question is used in the following exam:

Programming extension demo by Christian Lawson-Perfect in Programming extension.

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Error

Sum of triangular numbers (with optional steps)

Metadata

Taxonomy: mathcentre

Taxonomy: Kind of activity

Taxonomy: Context

Contributors

History

Comment

Checkpoint description

Christian Lawson-Perfect 1 year, 10 months ago

Christian Lawson-Perfect commented 3 years, 1 month ago

George Stagg commented 3 years, 1 month ago

Chris Graham commented 3 years, 1 month ago

Chris Graham 3 years, 1 month ago

Error in variable testing condition

Error

Warning

Generated value: `integer`

Parts

Code

Loading...

Error

Sum of triangular numbers (with optional steps)

Metadata

Taxonomy: mathcentre

Taxonomy: Kind of activity

Taxonomy: Context

Contributors

History

Comment

Checkpoint description

Christian Lawson-Perfect 1 year, 10 months ago

Christian Lawson-Perfect commented 3 years, 1 month ago

George Stagg commented 3 years, 1 month ago

Chris Graham commented 3 years, 1 month ago

Chris Graham 3 years, 1 month ago

Error in variable testing condition

Error

Warning

Generated value: integer

Parts

Code

Generated value: `integer`