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mrcactu5

470 karma · joined December 5, 2012

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mrcactu5··on NumPy 1.20
There's a random shuffle function. Instead of writing one out using an algorithms textbook. Lots of data types get randomly shuffled during coding.

Shuffles arrays and lists. https://numpy.org/doc/stable/reference/random/generated/nump...

mrcactu5··on Quiver: A modern commutative diagram editor
has anyone seen "The Stacks Project" ? it's very technical but it's nice and collaborative https://stacks.math.columbia.edu/
mrcactu5··on Introduction to Linear Algebra for Applied Machine Learning with Python
here's a Linear Algebra course from Columbia University with a bit of computer science emphasis. https://tonydear.github.io/teaching/coms3251
mrcactu5··on Open textbooks approved by the American Institute of Mathematics
there are lists of math and physics textbooks on github. maybe these are helpful https://github.com/carlosal1015/Books
mrcactu5··on Why introductory chemistry is boring: a long-term historical perspective
what are the good freshmen level chemistry textbooks these days ?
mrcactu5··on In New York, Making Ends Meet on a 5-Cent Recycling Deposit
Everybody drinks soda misses the garbage can, so these people are making the bottle and can recycling market more efficient.
mrcactu5··on Visual6502 Remix
if all I want to to is build a Super Mario clone is the knowledge of the 6502 assembly language still necessary ?
mrcactu5··on Mathematicians Cut Apart Shapes to Find Pieces of Equations
Here's a scissor's congruence app on github

https://dmsm.github.io/scissors-congruence/

mrcactu5··on Solving Every Sudoku Puzzle (2006)
last year's US Sudoku Team Qualifier was held online at some point. Possibly in May or July.

http://wpc.puzzles.com/ussq2019/

mrcactu5··on Levenshtein Distance
is Levenshtein distance a "metric" in the sense of "metric spaces"? For example, the TaxiCab metric.

https://en.wikipedia.org/wiki/Taxicab_geometry

https://en.wikipedia.org/wiki/Metric_(mathematics)

Also, this looks like could be related to the Hamming Code ? Error correcting codes.

https://en.wikipedia.org/wiki/Hamming_distance

mrcactu5··on The Feynman Lectures on Physics: The Principle of Least Action (1963)
This shows the thrown ball (from Freshman physics) should follow a parabolic arc rather than a straight line.

https://en.wikipedia.org/wiki/Principle_of_least_action

mrcactu5··on Wavelets (1994) [pdf]
how does this compare to Fast Fourier transform ?

https://en.wikipedia.org/wiki/Fast_Fourier_transform

Or the Discrete Cosine Transform ?

https://en.wikipedia.org/wiki/Discrete_cosine_transform

Or the Gabor Transform ?

https://en.wikipedia.org/wiki/Gabor_transform

mrcactu5··on The Feynman Lectures on Physics: Algebra (1963)
He does a numerical computation of the complex powers of 10 (to five decimal places) and they still are on the unit circle. And this was done in 1963.
mrcactu5··on “Culture fit” is a two way street (2018)
http://mathworld.wolfram.com/PerpendicularBisector.html
mrcactu5··on Regex for Noobs – An Illustrated Guide
https://regexper.com/
mrcactu5··on Calculus for Beginners and Artists (2003)
Robert Ghrist has written an colorful and innovative calculus text.

https://www.math.upenn.edu/~ghrist/calculus.html

https://www.math.upenn.edu/~ghrist/notes.html

https://sites.math.washington.edu/~morrow/334_13/FLCT.pdf

mrcactu5··on Aceto: A programming language based on a 2D Hilbert curve grid
what motivates all these esolangs? these fractals tend to be coding exercises.

https://en.wikipedia.org/wiki/Hilbert_curve

https://en.wikipedia.org/wiki/Dragon_curve

mrcactu5··on Words That Are Their Own Opposites (2015)
these are called "Janus words" or self-antonyms. Such as "flammable" and "inflammable".

https://en.wikipedia.org/wiki/Auto-antonym

mrcactu5··on CS Unplugged: Teaching material for CS using cards, string and crayons
does the United States have any such programs?
mrcactu5··on Two-thirds of American employees regret their college degrees
i got into a nice college, and they even gave us financial aid. the job market was unforgiving.
mrcactu5··on Use Coq in Your Browser: The Js Coq Theorem Prover Online
i've always wondered how web and functional programming interact. there's, for example TypeScript and Elm. These are not designed for mathematical proofs.

https://www.typescriptlang.org/ https://elm-lang.org/

mrcactu5··on Matrices as Tensor Network Diagrams
here are some pages that might be relevant

https://ncatlab.org/nlab/show/tensor+network https://ncatlab.org/nlab/show/string+diagram

mrcactu5··on God's Number Is 20 (2010)
Here's some notes from Harvard on how to count Rubik's Cube positions with Group Theory

The number is: 2^(12)3^88!*12!

http://www.math.harvard.edu/~jjchen/docs/Group%20Theory%20an...

mrcactu5··on Human psychology and behavioral studies overlook 85 percent of people
a simple arithmetic computation shows that Europe has 750 million people, and the world has 8 billion people. That's 1/10 of the population. We neglect about 90% of people in... anything. South America has 500 million people, so they should get a comparable share, and Africa has 1.2 billion.

So just by simple fractions we know something is off. A more careful study by subject and region could be required.

mrcactu5··on Analyzing the chords of 1300 popular songs for patterns
Flow Machines is an AI music generator http://www.flow-machines.com/
mrcactu5··on Anglican: A Probabilistic Programming System
why did they pick Clojure to do probabilistic programming?

btw, Python programmers have the option of pymc3 https://docs.pymc.io/

mrcactu5··on Ask HN: I've been a programmer for 6 years, and I can't solve basic CS problems
at least on StackOverflow "computer science" and "computer programming" get different pages:

https://cs.stackexchange.com/

https://softwareengineering.stackexchange.com/

mrcactu5··on California just replaced cash bail with algorithms
Machine Learning Algorithms are severely racist towards defendants. We know, for example, that AI algorithms mistake Black people for primates... but they are no more racist than the criminal justice system at large. And they have a better chance of getting fixed.

https://www.nytimes.com/2016/06/26/opinion/sunday/artificial...

mrcactu5··on TinyEditor: A functional HTML/CSS/JS editor in less than 400 bytes
github says 407 bytes... how is he doing that?? my HTML / CSS is nowhere near that level
mrcactu5··on Amazon Dark Patterns
if you are Amazon you don't have time to read all the reviews carefully. How do you detect such artificial "gaming" behavior? It's natural behavior for the sellers to try to boost their reviews (at the consumers expense).
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