new map projection i'm developing. using this on a whole hemisphere is too much distortion for quantitative purposes, but aesthetically this is pretty nice. it could be the logo of a pan-american NGO or something like that.

👎: abbreviating "if and only if" as iff
👍: abbreviating "if and only if" as if'n

a quadrilateral on the sphere having opposing sides of equal length isn't really a parallellogram, because there are no parallel lines on a sphere. such a shape that also has equal vertex angles isn't really a rectangle, because its angles are all >90°. you can in fact, have a rectangular triangle on the sphere, i.e. a triangle whose angles are all right

what to call such shapes? i should talk to my sister, she's an expert in the nomenclature of simple shapes. that is, she teaches kindergarten

Hypothesis: A Muppet Christmas Carol and Rare Exports are basis vectors which span the space of Christmas movies.

This plot I made earlier looks like The Great Wave off Kanagawa as reproduced on a broken copy machine

ooh spyder 4 is out, and it has a functional dark mode!

one feature I wish existed in numpy is the ability to name an axis of a multidimensional array. instead of axis 0, 1, 2, you could have axis 'sample_num', 'timestep', 'xyz'. broadcasting could look for axes with the same name, instead of using arbitrary broadcasting rules that I can never remember. the @ operator could become a form of einstein summation: multiply and sum over the shared axis names. this also makes the analogies between arrays and database tables more obvious.

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
.png

practical ways i've found to deal with numpy arrays with more than two axes:
1. einsum
2. reshape it to the axes you actually need and then reshape it back when you're done
3. weeping, gnashing of teeth

Ah yes I'll have the macmac + maccheese +cheesemac + cheesecheese

is pretty great. Why have I been trying to do GIS stuff in just R for so long?

Just got back from seeing John Urschel give a talk. I didn't know Martin Gardner was such a big influence on him. And they say recreational math is pointless...

ah, so Sabine Hossenfelder has reached the "half-baked political opinions" stage of the academic life cycle

Support vector machines
All vector machines are valid

Show more
Mathstodon

A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes. Use \( and \) for inline LaTeX, and \[ and \] for display mode.