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What are the differences between a multidimensional array and an array of arrays in C#?
... implementation they are not.
23.084 16.634 15.215 15.489 14.407 13.691 14.695 14.398 14.551 14.252
25.782 27.484 25.711 20.844 19.607 20.349 25.861 26.214 19.677 20.171
5.050 5.085 6.412 5.225 5.100 5.751 6.650 5.222 6.770 5.305
The first row are timings ...
Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
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91
The subtle difference is that 3NF makes a distinction between key and non-key attributes (also ...
How to calculate moving average using NumPy?
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Is R's apply family more than syntactic sugar?
...me(z <- lapply(y, foo))
# user system elapsed
# 2.89 0.00 2.91
system.time(z <- vapply(y, foo, numeric(1)))
# user system elapsed
# 1.35 0.00 1.36
Jan. 1, 2020 update:
system.time({z1 <- numeric(1e6); for(i in seq_along(y)) z1[i] <- foo(y[i])})
# user syst...
What is the most efficient/elegant way to parse a flat table into a tree?
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Leniel Maccaferri
91.3k4040 gold badges331331 silver badges445445 bronze badges
answered Dec 22 '10 at 4:31
bobobobobob...
What's the difference between UTF-8 and UTF-8 without BOM?
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91
Here are examples of the BOM usage that actually cause real problems and yet many people don't ...
Is XSLT worth it? [closed]
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91
So much negativity!
I've been using XSLT for a good few years now, and genuinely love it. The ...
How come a non-const reference cannot bind to a temporary object?
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Tony DelroyTony Delroy
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Fastest way to determine if an integer's square root is an integer
...re than the benefit one gets, so I use bit tricks involving 255 = 2^8-1 to compute the residue. (For better or worse, I am not using the trick of reading individual bytes out of a word, only bitwise-and and shifts.)
int64 y = x;
y = (y & 4294967295LL) + (y >> 32);
y = (y & 65535) + (...
Twitter image encoding challenge [closed]
...thmetic for its string encoding.
I based my solution off of fractal image compression, with a few unique twists. The basic idea is to take the image, scale down a copy to 50% and look for pieces in various orientations that look similar to non-overlapping blocks in the original image. It takes a ...