Problem 258. linear least squares fitting

Created by Tomasz

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Last Solution submitted on Oct 13, 2021

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Alfonso Nieto-Castanon on 9 Jan 2013

your functions are not all truly 'vectorized'; I would change @(x)1 to @(x)ones(size(x)) for a more consistent 'vectorized' behavior...

Tomasz on 10 Jan 2013

Yup, you're right. I made the adjustment...

Alfonso Nieto-Castanon on 10 Jan 2013

not meaning to be picky, but in the third test you might want to use aref.' instead of aref' (if x take negative values, which occurs at random for this test, then log(x) takes complex values, and the aref' portion takes the conjugate of the complex valued results); perhaps it is simpler to make sure x takes only positive values...

Alfonso Nieto-Castanon on 10 Jan 2013

and nice problem, by the way!

Tomasz on 10 Jan 2013

Thanks! Nice catch, I fixed that second issue too (those randomized tests have their drawbacks)

Tikay on 26 Oct 2020

Sorry, but I can not understand the problem to solve.
Can anyone explain to me, please?

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Problem 258. linear least squares fitting

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