
Linear Algebra Review and Reference (2012) [pdf] - dstein64
http://cs229.stanford.edu/section/cs229-linalg.pdf
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denzil_correa
I have a gripe with references in general. Most references are just reference
formulae and symbol manipulation. In general, they are the form of - We call
this as Title X. In this X, you have ABC; you then do MNO* operations to get
YZ. There's hardly context of when to use them or what they really mean. "A
Mathematician's Lament" by Paul Lockhart hits hard here.

[https://www.maa.org/external_archive/devlin/LockhartsLament....](https://www.maa.org/external_archive/devlin/LockhartsLament.pdf)

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ryanmonroe
References are not made to learn from, they are made to refer back to. If you
look at the URL you will see that this reference in particular is on the page
for CS229, which lists knowledge of basic linear algebra as a prerequisite. I
really don't think this was made with the intention of anyone using it to
learn linear algebra.

~~~
denzil_correa
Yes, references are to "refer back to" \- the key part here is that what are
they meant to "refer back to"? A set of formulae, symbol manipulation or how
to apply functions? References should be notes that help you recollect what
you'd learn. In this case, the references recollect a set of manipulation of
symbols which happen to be Linear Algebra.

Do note that I am talking about "Reference Manuals" in general and not this
particular CS 229 manual.

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math_and_stuff
The Lagrangian on the last page associated with computing the maximal
eigenpair should probably have the term lamba (x^T x - 1), not lamba x^T x.
The latter gets the gradient with respect to x right, but not the gradient
with respect to lambda, and it would provide the wrong dual problem.

