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What is the difference between _tmain() and main() in C++?
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_tmain does not exist in C++. main does.
_tmain is a Microsoft extension.
main is, according to the C++ standard, the program's entry point.
It has one of these two signatures:
int main();
int main(int argc, char* argv[]);...
How to use filter, map, and reduce in Python 3
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@Breezer actually i**3 will call i.__pow__(3) and i*i*i i.__mul__(i).__mul__(i) (or something like that). With ints it doesn't matter but with numpy numbers/custom classes it might even produce different results.
– syntonym
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Do try/catch blocks hurt performance when exceptions are not thrown?
...TryCatch() cil managed
{
// Code size 32 (0x20)
.maxstack 8
IL_0000: nop
IL_0001: ldstr "SIN(1) = {0} - No Try/Catch"
IL_0006: ldc.r8 1.
IL_000f: call float64 [mscorlib]System.Math::Sin(float64)
IL_0014: box [mscorlib]System.Double
IL_0019: call ...
Is there a range class in C++11 for use with range based for loops?
...C++ standard library does not have one, but Boost.Range has boost::counting_range, which certainly qualifies. You could also use boost::irange, which is a bit more focused in scope.
C++20's range library will allow you to do this via view::iota(start, end).
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How to printf uint64_t? Fails with: “spurious trailing ‘%’ in format”
I wrote a very simple test code of printf uint64_t:
3 Answers
3
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Map vs Object in JavaScript
...often a pain with non-scalar types where you have to deal with things like PHP merges Array/Map with Object using A/M for properties and JS merges Map/Object with Array extending M/O. Merging complex types is the devil's bane of high level scripting languages.
So far these are largely issues around ...
What's the best way to inverse sort in scala?
...way of changing the sign, if you sort by some numeric value
list.sortBy(- _.size)
More generally, sorting may be done by method sorted with an implicit Ordering, which you may make explicit, and Ordering has a reverse (not the list reverse below)
You can do
list.sorted(theOrdering.reverse)
If...
import module from string variable
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The __import__ function can be a bit hard to understand.
If you change
i = __import__('matplotlib.text')
to
i = __import__('matplotlib.text', fromlist=[''])
then i will refer to matplotlib.text.
In Python 2.7 and Python ...
How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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Why does running the Flask dev server run itself twice?
...Flask with the development server when you call app.run().
See the restart_with_reloader() function code; your script is run again with subprocess.call().
If you set use_reloader to False you'll see the behaviour go away, but then you also lose the reloading functionality:
app.run(port=4004, debu...