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What exactly does big Ө notation represent?
...s than n0). The bounds hold for all n ≥ n0, but not below n0 where lower order terms become dominant.
– bain
Dec 4 '16 at 11:28
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How can I get dictionary key as variable directly in Python (not by searching from value)?
...f you want to print key and value, use the following:
for key, value in my_dict.iteritems():
print key, value
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Is it possible to declare two variables of different types in a for loop?
...:
auto [vec, i32] = std::tuple{std::vector<int>{3, 4, 5}, std::int32_t{12}}
A specific application of this is iterating over a map, getting the key and value,
std::unordered_map<K, V> m = { /*...*/ };
for (auto& [key, value] : m) {
// ...
}
See a live example here
C++14: ...
Getting Django admin url for an object
...written a small filter that I'd use like this: <a href="{{ object|admin_url }}" .... > ... </a>
9 Answers
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Starting python debugger automatically on error
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You can use traceback.print_exc to print the exceptions traceback. Then use sys.exc_info to extract the traceback and finally call pdb.post_mortem with that traceback
import pdb, traceback, sys
def bombs():
a = []
print a[0]
if __name__ == '...
Code Golf: Lasers
...amp;!ge,$s=$r+=99for<>;%d='>.^1<2v3'=~/./g;($r)=grep$d|=$d{$t{$_}},%t;
{$_=$t{$r+=(1,-99,-1,99)[$d^=3*/\\/+m</>]};/[\/\\ ]/&&redo}die/x/?true:false,$/
The first line loads the input into %t, a table of the board where $t{99*i+j} holds the character at row i,column j. Then...
Elegant way to invert a map in Scala
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Assuming values are unique, this works:
(Map() ++ origMap.map(_.swap))
On Scala 2.8, however, it's easier:
origMap.map(_.swap)
Being able to do that is part of the reason why Scala 2.8 has a new collection library.
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What is the difference between a field and a property?
...It is private to your class and stores the actual data.
private string _myField;
// this is a property. When accessed it uses the underlying field,
// but only exposes the contract, which will not be affected by the underlying field
public string MyProperty
{
get
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Why can't I use a list as a dict key in python?
...le, it'll work correctly with classes that have a custom comparison method __eq__. But if you convert them to strings, everything is compared by its string representation.
– Aran-Fey
May 20 '18 at 12:50
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fancybox2 / fancybox causes page to to jump to the top
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The problem is that fancy box changes the overflow value of the body in order to hide the browser scrollbars.
As Dave Kiss points out, we can stop fancy box from doing this by adding the following parameters:
$('.image').fancybox({
padding: 0,
helpers: {
overlay: {
locked: false
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