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sbi
searching PlanetScale…
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5 ms
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Ayasdi Accelerates with $55M Investment
(ayasdi.com)
1 points
by
sbi
12y ago
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0 comments
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The Real Reason for L-1B Visa Denial Rates Being Higher for Indian Nationals
(blog.cyrusmehta.com)
1 points
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sbi
12y ago
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sbi
12y ago
Heapsort has poor cache performance though. Its asymptotic complexity depends on the assumption that memory access is O(1), which is not borne out in practice.
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sbi
12y ago
Webster's Dictionary does not discuss the pejorative use of the word "ghetto" and in any case is not an arbiter of racism.
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sbi
12y ago
What charming casual racism. "It's pretty ghetto" ... "The ghetto way is just to run this on a machine" ... "The ghetto reversing is to run strings."
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sbi
12y ago
Thanks for explaining that to me. To add to the confusion, tabasco is also a pepper cultivar named after the Mexican state.
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sbi
12y ago
Tabasco is a state in Mexico, though; how were its trademark owners able to obtain the name?
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sbi
12y ago
There are many different versions of awk: gawk, (BSD) nawk, mawk, etc. I think OS X uses nawk, but mawk is reputedly faster. Gawk is definitely slower than both mawk. I'm not surprised that Perl is faster though.
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sbi
12y ago
Probably not, but in some cases sed and AWK might be faster. I am a big fan of AWK. It is limited in some ways that make it impractical to use for really serious programs, but it is very expressive. Look at [1, 2]. [1]: http://c2
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sbi
12y ago
The data from the study are available on the PLoS website. The authors coded incomplete documents as mistakes---some participants submitted empty LaTeX documents for the table exercise with hundreds of "mistakes." Since the LaTeX
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sbi
12y ago
Looking over their data, it seems that they coded incomplete text as an error. So, for example, participants 34 and 37 completed none of the table exercise and were coded as having produced 513 errors (both were LaTeX users). This accounts
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sbi
12y ago
Doesn't std::list<T> generate different code for each type T, at least naively? The generated code could end up taking up more space even if the data structures on which it operates look the same in memory.
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sbi
12y ago
This article correctly observes that "many resources are not plain memory" and then goes on to advise users to close() a file in a destructor. However, one of the ways that files are not like memory is that while free() can never
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sbi
13y ago
The Kelly criterion doesn't quite apply in this problem, since you are asked to optimize a more conservative strategy, namely to guarantee (with high probability) a certain amount of winnings rather than maximize log(winnings). In fact
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sbi
13y ago
Typically you wouldn't use lgamma to compute exact values of factorials at all. For a real world example of this function in action, look at John D. Cook's blog: [1]: http://www.johndcook.com/blog/2012/07
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sbi
13y ago
I explained this in a reply below, but this is a linear-algebraic technique. The matrix A = [0 1; 1 1] satisfies the relation A^2 - A - 1 = 0. (In fact, if you think of A as a lag operator, this is the definition of Fibonacci numbers!) You
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sbi
13y ago
You are correct that this code uses "Russian Peasant Multiplication." The question is: what is being exponentiated? One choice is the matrix A = [0 1; 1 1], whose powers are A^n = [F_{n-1} F_n; F_n F_{n+1] if we compute those powe
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sbi
13y ago
Thank you for the reference. The algorithm in the parent comment is not actually matrix exponentiation but the "fast doubling algorithm" in Minase's terminology, where you exponentiate the matrix algebraically using the Cayle
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sbi
13y ago
Which reference?
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sbi
13y ago
The "right" way to generate Fibonacci numbers is not via the closed form, but by exponentiation of the matrix A = [0 1; 1 1] that defines Fibonacci numbers as an element of its endomorphism ring Z[x]/(x^2 - x - 1). This doesn
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sbi
13y ago
There are tools for standardizing C formatting. Another poster mentioned indent. Clang-format [1] is very good, works with C++ as well as C, and has great editor integration. You can choose among predefined style (e.g. Google, Mozilla, LLVM
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sbi
13y ago
Thanks; I had searched on pgp.mit.edu for the primary key but forgot to add the hex prefix 0x. Curiously, the 1024 bit DSA key used for some previous releases (0x7f4d66451ebcab3a) has been signed by "Someone at Mozilla Should Sign the
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sbi
13y ago
I see that Mozilla is now signing hashes of Firefox downloads with a 4096-bit RSA key. But the key used to sign firefox-23.0.tar.bz2 (id 0x057CC3EB15A0A4BC) is only self-signed and was created three weeks ago. It's not on pgp.mit.edu.
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sbi
13y ago
The "5,031" statistic is ludicrous. At least that many people were killed by lynching alone, not to mention Wounded Knee.
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sbi
13y ago
These are quotes from the Bolt drama "A Man for All Seasons," not Sir Thomas More himself.
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sbi
13y ago
I'm surprised nobody has mentioned Koblitz and Menezes in this thread. Unfortunately, the mathematical literature is littered with insecure, but "provably secure," cryptosystems. [1] http://anotherlook.ca/ [2
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sbi
13y ago
NRO has some Flash games. There's also ATF for kids, CIA for kids, US Marshals Service for kids ...
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sbi
13y ago
The campy NSA kids' website has nothing to do with recruitment; the Clinton administration required all Federal agencies to create websites for children in an April 18, 1997 memorandum [1]. This is clearly spelled out in the terms-of-u
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sbi
13y ago
Two notes: factoring polynomials over finite fields isn't hard (look up the Berlekamp algorithm or Cantor-Zassenhaus for starters). Second, I believe the system you've described doesn't satisfy your property (b). Quantities such as M[1]C[0]
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sbi
13y ago
If you believe that Lie theory is "pratical," then yes. See John Baez's excellent survey: http://math.ucr.edu/home/baez/octonions/
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