
Explained Visually is now open source - tilt
https://github.com/vicapow/explained-visually
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daniel-levin
I just recently discovered an awesome visual intuition for what a determinant
is, and why one cannot solve a linear system with a zero determinant. I'd love
to contribute to this!

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hypeibole
You've piqued my interest.

Would you mind explaining it in a few words?

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daniel-levin
In 2 dimensions, the absolute value of a determinant of a matrix is just the
area of the parallelogram subtended by the row vectors of the matrix. If this
area is zero, it means that the vectors are co-linear. And of course the
intersection of co-linear vectors is an infinite set (in R^n anyways). The
same idea holds in higher dimensions, with the 3d case being similarly
possible to visualise (as a volume). Since the unique solution of a linear
system is the point at which a bunch of lines/planes/hyperplanes meet, a zero
determinant implies a zero area which means that at least two vectors are
coincident and hence there are infinitely many solutions.

[1]
[https://www.math.ucdavis.edu/~daddel/linear_algebra_appl/App...](https://www.math.ucdavis.edu/~daddel/linear_algebra_appl/Applications/Determinant/Determinant/node4.html)

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jcoffland
Awesome site. Great way to fill in some of the gaps in my math education.

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michaelbuddy
my opinion, the lack of comments come from that the site isn't very intuitive
for knowing what this is all about. maybe just a clean description or use case
scenario is in order.

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glitch
Admittedly the first sentence in the README.md points to relevant information
([http://setosa.io/ev/](http://setosa.io/ev/)) However, yes, they should have
included the one sentence description on that page it links to in the
README.md itself.

Explained Visually (EV) is an experiment in making hard ideas intuitive
inspired the work of Bret Victor's Explorable Explanations. See
[http://worrydream.com/ExplorableExplanations/](http://worrydream.com/ExplorableExplanations/)
to learn more about Explorable Explanations.

See "Media for Thinking the Unthinkable" (Bret Victor, 2013)
[https://vimeo.com/67076984](https://vimeo.com/67076984) and videos from
[https://vimeo.com/worrydream/videos](https://vimeo.com/worrydream/videos) for
more context. Also,
[http://explorableexplanations.com](http://explorableexplanations.com) (by
Nicky Case) is a.... page that exists.

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vicapow
Pull request? :)

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noir_lord
These are awesome and kudos for open sourcing it, this is the kind of material
I expected all school kids to be learning from by now (based mostly on sci-
fi).

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joshmn
63 points, not a single comment...

Weirdest display of crickets I've seen on the internet in a while.

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pcunite
Comment #3

