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How can I profile Python code line-by-line?
I've been using cProfile to profile my code, and it's been working great. I also use gprof2dot.py to visualize the results (makes it a little clearer).
...
Multiple aggregations of the same column using pandas GroupBy.agg()
Is there a pandas built-in way to apply two different aggregating functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
...
Difference between this and self in JavaScript
... // true
If you're using a function that is executed in the global scope and is not in strict mode, this defaults to window, and therefore
function foo() {
console.log(
window.self === window, // is self window?
window.self === this, // is self this?
this === window ...
What is an uninterruptible process?
Sometimes whenever I write a program in Linux and it crashes due to a bug of some sort, it will become an uninterruptible process and continue running forever until I restart my computer (even if I log out). My questions are:
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CMake output/build directory
I'm pretty new to CMake, and read a few tutorials on how to use it, and wrote some complicated 50 lines of CMake script in order to make a program for 3 different compilers. This probably concludes all my knowledge in CMake.
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What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
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What is the advantage of using forwarding references in range-based for loops?
...dvantage I can see is when the sequence iterator returns a proxy reference and you need to operate on that reference in a non-const way. For example consider:
#include <vector>
int main()
{
std::vector<bool> v(10);
for (auto& e : v)
e = true;
}
This doesn't compi...
How to get StackPanel's children to fill maximum space downward?
I simply want flowing text on the left, and a help box on the right.
4 Answers
4
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When is memoization automatic in GHC Haskell?
... in foldl' (+) 0 (y ++ [x])
GHC might notice that y does not depend on x and rewrite the function to
f = let y = [1..30000000] in \x -> foldl' (+) 0 (y ++ [x])
In this case, the new version is much less efficient because it will have to read about 1 GB from memory where y is stored, while th...
Does const mean thread-safe in C++11?
...ad-safe in C++11. Is that true?
It is somewhat true...
This is what the Standard Language has to say on thread-safety:
[1.10/4]
Two expression evaluations conflict if one of them modifies a memory location (1.7) and the other one accesses or modifies the same memory location.
[1.10/21]
The executi...