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Get a random boolean in python?
...ter
$ python -m timeit -s "import random" "random.choice([True, False])"
1000000 loops, best of 3: 0.904 usec per loop
$ python -m timeit -s "import random" "random.choice((True, False))"
1000000 loops, best of 3: 0.846 usec per loop
$ python -m timeit -s "import random" "random.getrandbits(1)"
10...
Resizing an image in an HTML5 canvas
...lement them yourself then! Oh come on, we're entering the new age of Web 3.0, HTML5 compliant browsers, super optimized JIT javascript compilers, multi-core(†) machines, with tons of memory, what are you afraid of? Hey, there's the word java in javascript, so that should guarantee the performance,...
Matplotlib tight_layout() doesn't take into account figure suptitle
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10 Answers
10
Active
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How to print binary tree diagram?
...l - level;
int endgeLines = (int) Math.pow(2, (Math.max(floor - 1, 0)));
int firstSpaces = (int) Math.pow(2, (floor)) - 1;
int betweenSpaces = (int) Math.pow(2, (floor + 1)) - 1;
BTreePrinter.printWhitespaces(firstSpaces);
List<Node<T>> newNodes ...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
...ications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
I spent several days to solve this problem. I have tested many approaches that have been mentioned in different web sites, but non of them worked....
Black transparent overlay on image hover with only CSS?
... the img element itself, see.
.image {
position: relative;
width: 400px;
height: 400px;
}
Give the child img element a width of 100% of the parent and add vertical-align:top to fix the default baseline alignment issues.
.image img {
width: 100%;
vertical-align: top;
}
As for th...
How to Rotate a UIImage 90 degrees?
...rientationUp (portrait) that I would like to rotate counter-clockwise by 90 degrees (to landscape). I don't want to use a CGAffineTransform . I want the pixels of the UIImage to actually shift position. I am using a block of code (shown below) originally intended to resize a UIImage to do this...
In C++, is it still bad practice to return a vector from a function?
...arrays—in many programming languages. Is this style now acceptable in C++0x if the class has a move constructor, or do C++ programmers consider it weird/ugly/abomination?
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Why are elementwise additions much faster in separate loops than in a combined loop?
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10 Answers
10
Active
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How to reorder data.table columns (without copying)
...ta.table(a = 1:3, b = 3:1, c = runif(3))
x
# a b c
# [1,] 1 3 0.2880365
# [2,] 2 2 0.7785115
# [3,] 3 1 0.3297416
setcolorder(x, c("c", "b", "a"))
x
# c b a
# [1,] 0.2880365 3 1
# [2,] 0.7785115 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all s...