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List comprehension vs map
...
10000 loops, best of 3: 181/118/123 usec per loop ^^^^^^^^^^^^^^^^^^
for list(<generator>), probably optimized
% python3 -mtimeit -s 'xs=range(1000)' 'f=lambda x:x' 'z=list(f(x) for x in xs)' ...
Android: Want to set custom fonts for whole application not runtime
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123
+50
EDIT: S...
What is an existential type?
...ing> mc1 = new MyClass("foo");
MyClass<Integer> mc2 = new MyClass(123);
MyClass<?> mc3 = MyClass.secretMessage();
From the perspective of a client of MyClass, T is universal because you can substitute any type for T when you use that class and you must know the actual type of T whe...
What is a NullPointerException, and how do I fix it?
...c static void main(String[] args) {
Printer printer = new Printer("123");
printer.print();
}
}
See also:
Avoiding “!= null” statements in Java?
I still can't find the problem
If you tried to debug the problem and still don't have a solution, you can post a question for...
How to “perfectly” override a dict?
...e accepted answer remove the redundant dict?
– Seanny123
Mar 8 '17 at 5:23
1
Two ways that immedi...
How to make good reproducible pandas examples
... data and results.
import numpy as np
import pandas as pd
np.random.seed(123)
A kitchen sink example
Here's an example showing a variety of things you can do. All kinds of useful sample dataframes could be created from a subset of this:
df = pd.DataFrame({
# some ways to create random d...
What are the differences between Generics in C# and Java… and Templates in C++? [closed]
...e from this situation, consider the following code:
Y<int>::my_type(123);
This code statement is perfectly valid and tells C++ to execute the function call to Y<int>::my_type. However, if my_type is not a function but rather a type, this statement would still be valid and perform a sp...
Running Bash commands in Python
...r((i=1;i<=$#;i++)); do
# Arrays are Bash-only
array[i]+=123
done''',
shell=True, check=True,
executable='/bin/bash')
A subprocess is separate from its parent, and cannot change it
A somewhat common mistake is doing something like
subprocess.run('foo=bar', shell=Tru...
Pretty-print C++ STL containers
...sert("hello");
j.insert("world");
double k[] = { 1.1, 2.2, M_PI, -1.0/123.0 };
std::cout << i << "\n" << j << "\n" << k << "\n";
}
It currently only works with vector and set, but can be made to work with most containers, just by expanding on the IsConta...
For-each over an array in JavaScript
...
123
Loop backwards
I think the reverse for loop deserves a mention here:
for (var i = array.leng...