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[] and {} vs list() and dict(), which is better?
I understand that they are both essentially the same thing, but in terms of style, which is the better (more Pythonic) one to use to create an empty list or dict?
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Ternary operator is twice as slow as an if-else block?
... answer this question, we'll examine the assembly code produced by the X86 and X64 JITs for each of these cases.
X86, if/then
32: foreach (int i in array)
0000007c 33 D2 xor edx,edx
0000007e 83 7E 04 00 cmp dword ptr [esi+4],0
00000082 ...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
... trade off memory for speed (assuming your L1 Data Cache is large enough), and reverse 16 bits at a time with a 64K-entry lookup table.
Others
Simple
unsigned int v; // input bits to be reversed
unsigned int r = v & 1; // r will be reversed bits of v; first get LSB of v
int s = sizeof(v...
how to draw smooth curve through N points using javascript HTML5 canvas?
...nts), but for my purposes (a drawing application), it's good enough for me and visually you can't tell the difference. There is a solution to go through all the sample points, but it is much more complicated (see http://www.cartogrammar.com/blog/actionscript-curves-update/)
Here is the the drawing...
Why do indexes in XPath start with 1 and not 0?
Some colleagues and I were comparing past languages we had programmed in and were talking about our experience with VBScript with its odd features such as 1-based index instead of 0-based indexes like almost every other language has, the reasoning being that it was a language for users (e.g....
Gradients on UIView and UILabels On iPhone [duplicate]
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You could also use a graphic image one pixel wide as the gradient, and set the view property to expand the graphic to fill the view (assuming you are thinking of a simple linear gradient and not some kind of radial graphic).
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Searching for UUIDs in text with regex
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@cyber-monk: [0-9a-f] is identical to [a-f0-9] and [0123456789abcdef] in meaning and in speed, since the regex is turned into a state machine anyway, with each hex digit turned into an entry in a state-table. For an entry point into how this works, see en.wikipedia.org/wi...
How to style dt and dd so they are on the same line?
... <dd>Mercury (0.4 AU from the Sun) is the closest planet to the Sun and the smallest planet.</dd>
<dt>Venus</dt>
<dd>Venus (0.7 AU) is close in size to Earth, (0.815 Earth masses) and like Earth, has a thick silicate mantle around an iron core.</dd>
<...
Add column with constant value to pandas dataframe [duplicate]
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The reason this puts NaN into a column is because df.index and the Index of your right-hand-side object are different. @zach shows the proper way to assign a new column of zeros. In general, pandas tries to do as much alignment of indices as possible. One downside is that when indice...
What does multicore assembly language look like?
...that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or multi ...