Member of the e-learning unit in Newcastle University's School of Mathematics and Statistics.

Lead developer of Numbas.

I'm happy to answer any questions - email me.

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Christian Lawson-Perfect commented on Basic R: Part 2a 9 years, 3 months ago

I don't think this contains any errors any more, but it certainly could do with explaining itself a bit better.

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Christian Lawson-Perfect on Basic R: Part 2a 9 years, 3 months ago

Gave some feedback: Needs to be tested

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Christian Lawson-Perfect on Amy's second copy of Question 10 length of vectors 9 years, 3 months ago

Saved a checkpoint:

Fixed the advice and the definition of x.

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Christian Lawson-Perfect on Amy's copy of Question 10 length of vectors 9 years, 3 months ago

Saved a checkpoint:

Fixed the advice.

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Christian Lawson-Perfect on Question 10 length of vectors 9 years, 3 months ago

Saved a checkpoint:

Fixed the advice.

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Christian Lawson-Perfect on Question 10 length of vectors 9 years, 3 months ago

Gave some feedback: Ready to use

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Christian Lawson-Perfect on Question 6 types of variables 9 years, 3 months ago

Saved a checkpoint:

Improved the advice.

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Christian Lawson-Perfect on Amy's copy of Question 10 length of vectors 9 years, 3 months ago

Saved a checkpoint:

The length of seq(a,b) is $b-a+1$, whereas this question thought it was $b-a$.

To fix it, I've subtracted one from the second argument to seq so that I don't have to change any variable definitions.

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Christian Lawson-Perfect on Basic R: Part 1 9 years, 3 months ago

Gave some feedback: Ready to use

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Christian Lawson-Perfect on Question 10 length of vectors 9 years, 3 months ago

Saved a checkpoint:

Fixed usage of c: seq(a,b) returns the numbers a to b inclusive, so its length is $a-b+1$. Since the rest of the question was set up to assume it's just $a-b$, I've subtracted 1 from the second argument to seq in the statement.