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Static methods in Python?
...e "top-level" function would have been clearer.
The following is verbatim from the documentation::
A static method does not receive an implicit first argument. To declare a static method, use this idiom:
class C:
@staticmethod
def f(arg1, arg2, ...): ...
The @staticmethod form is a functi...
Progress indicator during pandas operations
...or DataFrameGroupBy.progress_apply:
import pandas as pd
import numpy as np
from tqdm import tqdm
# from tqdm.auto import tqdm # for notebooks
df = pd.DataFrame(np.random.randint(0, int(1e8), (10000, 1000)))
# Create and register a new `tqdm` instance with `pandas`
# (can use tqdm_gui, optional kw...
Add swipe to delete UITableViewCell
...wCellEditingStyle.Delete) {
// handle delete (by removing the data from your array and updating the tableview)
}
}
Swift 3.0:
override func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
override func tableView(_ tableView: UITab...
What is the difference between a 'closure' and a 'lambda'?
...tion here. Instead of asking random programmers who learned about closures from practice with certain programming languages or other clueless programmers, take a journey to the source (where it all began). And since lambdas and closures come from Lambda Calculus invented by Alonzo Church back in the...
Can I call a constructor from another constructor (do constructor chaining) in C++?
...ature (called delegating constructors).
The syntax is slightly different from C#:
class Foo {
public:
Foo(char x, int y) {}
Foo(int y) : Foo('a', y) {}
};
C++03: No
Unfortunately, there's no way to do this in C++03, but there are two ways of simulating this:
You can combine two (or more...
Paste text on Android Emulator
... Level 19 (Android 4.4 - Kitkat) and higher, you can simply copy and paste from your desktop with your mouse or keyboard.
This feature was announced with Android Studio 2.3
share
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improve this ...
How does the Amazon Recommendation feature work?
...ata sources they have to mine...
Purchased shopping carts = real money from real people spent on real items = powerful data and a lot of it.
Items added to carts but abandoned.
Pricing experiments online (A/B testing, etc.) where they offer the same products at different prices and see the r...
What happens if a finally block throws an exception?
...- that's weird to say the least. Read on MSDN: AVOID throwing an exception from within Dispose(bool) except under ...
– Henk Holterman
Aug 14 '14 at 11:45
...
Understanding NSRunLoop
...eady.".
After doing so, it will then return to its loop, processing input from various sources, and "sleeping" if there is no work to do.
That's a pretty high level description (trying to avoid too many details).
EDIT
An attempt to address the comment. I broke it into pieces.
it means th...
Virtual functions and performance - C++
...loop, so the additional overhead per call was 7 nanoseconds per function.
From this I conclude: yes, virtual functions are much slower than direct functions, and no, unless you're planning on calling them ten million times per second, it doesn't matter.
See also: comparison of the generated assemb...