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Clean ways to write multiple 'for' loops
.../ ...
}
(or just:
for ( auto& elem: m ) {
}
if you have C++11.)
And if you need the three indexes during such iterations, it's
possible to create an iterator which exposes them:
class Matrix3D
{
// ...
class iterator : private std::vector<int>::iterator
{
Matri...
How do I see all foreign keys to a table or column?
...HEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_SCHEMA = '<database>' AND
REFERENCED_TABLE_NAME = '<table>';
For a Column:
SELECT
TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
FROM
INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABL...
How does the HyperLogLog algorithm work?
I've been learning about different algorithms in my spare time recently, and one that I came across which appears to be very interesting is called the HyperLogLog algorithm - which estimates how many unique items are in a list.
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Xcode 6: Keyboard does not show up in simulator
The keyboard does not show up when I run the simulator and click in the UITextView. How do I re-enable the keyboard?
13 Ans...
How to implode array with key and value without foreach in PHP
...
and another way:
$input = array(
'item1' => 'object1',
'item2' => 'object2',
'item-n' => 'object-n'
);
$output = implode(', ', array_map(
function ($v, $k) {
if(is_array($v)){
...
How to elegantly rename all keys in a hash in Ruby? [duplicate]
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Just use mappings[k] || k instead of mappings[k] above and it will leave keys not in the mapping as is.
– Mladen Jablanović
Nov 9 '10 at 20:26
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multiprocessing: How do I share a dict among multiple processes?
...rogram that creates several processes that work on a join-able queue, Q , and may eventually manipulate a global dictionary D to store results. (so each child process may use D to store its result and also see what results the other child processes are producing)
...
map function for objects (instead of arrays)
...For that matter I wanted to add another solution that returns a new object and leaves the original object as it is:
var myObject = { 'a': 1, 'b': 2, 'c': 3 };
// returns a new object with the values at each key mapped using mapFn(value)
function objectMap(object, mapFn) {
return Object.k...
How to make rpm auto install dependencies
...
Create a (local) repository and use yum to have it resolve the dependencies for you.
The CentOS wiki has a nice page providing a how-to on this. CentOS wiki HowTos/CreateLocalRepos.
Summarized and further minimized (not ideal, but quickest):
Creat...
Java 8 NullPointerException in Collectors.toMap
...ws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
...