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Tag Archives: Math
10 Awesome Theorems & Results
When I look back at various mathematical courses I took, most have at least one theorem that I really liked. Usually I like it because the proof has a surprising trick, sometimes it’s because of the unexpected conclusion, or maybe … Continue reading
The mathematics behind the solution for Challenge No. 5
If you take a look at the various solutions people proposed for the last challenge of generating a specific permutation, you’ll see that they are very similar. Most of them are based on some form of divmod usage. The reason … Continue reading
Posted in Challenges, computer science, Programming, Python
Tagged base systems, factorial, Knuth, Math, permutations
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Fast Peak Autocorrelation
So, I was at geekcon. It was a blast. There were many interesting projects, and I didn’t get to play with them all. I did get to work a bit on the Lunar Lander from last year, and this year … Continue reading
Posted in Algorithms, Math, Programming, Projects, Python, Utility Functions
Tagged autocorellation, automatic guitar improviser, geekcon, Math, pyimprov, signal processing
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Checking the ulam spiral
In the following post, the Ulam spiral is described. It’s a very simple object – write down consecutive natural numbers starting from 41 in a square spiral. Curiously, the numbers on the diagonal are primes: Reading this post, I immediately … Continue reading
Posted in Math, Programming, Python
Tagged Math, prime numbers, Programming, Python, Ulam spiral
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Fun with Matrices
I’ll let the code speak for itself: In [81]: m = Matrix(array([[1.0,1.0],[0.0,1.0]])) In [82]: def my_sqrt(x, num_iters): ….: r = 0.5*x ….: for i in xrange(num_iters): ….: r = 0.5*(r+x/r) ….: return r ….: In [83]: m*m Out[83]: … Continue reading
Computation over Zp in Python
Lately I’ve been working a lot on my Algebric Structures homework. One of the reasons I don’t blog as much as I should. While working on my homework, I had to factor some polynomials over Z5 – the field containing … Continue reading
Reachability on arbitrary maps
The other day I had an idea. What if you took a map of some country, and from each coordinate computed the time it took to any other coordinate. The basic assumptions are that you can drive on road by … Continue reading