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PHP Regex to get youtube video ID?
...o accomplish, use those.)
parse_url takes a string and cuts it up into an array that has a bunch of info. You can work with this array, or you can specify the one item you want as a second argument. In this case we're interested in the query, which is PHP_URL_QUERY.
Now we have the query, which is...
Most efficient way to cast List to List
... in the list is a SubClass.
Generic collections do not behave the same as arrays in Java. Arrays are covariant; that is, it is allowed to do this:
SubClass[] subs = ...;
BaseClass[] bases = subs;
This is allowed, because the array "knows" the type of its elements. If someone attempts to store so...
Iterate through a C++ Vector using a 'for' loop
...ething based on the vector. In Java I might do something like this with an ArrayList:
12 Answers
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Why is it OK to return a 'vector' from a function?
...
I think you are referring to the problem in C (and C++) that returning an array from a function isn't allowed (or at least won't work as expected) - this is because the array return will (if you write it in the simple form) return a pointer to the actual array on the stack, which is then promptly r...
Fastest way to convert string to integer in PHP
... 0.1502
intval(int): 0.65716 (438%)
(int) array("a", "b"): 0.91264
intval(array("a", "b")): 1.47681 (162%)
(int) "hello": 0.42208
intval("hello"): 0.93678 (222%)
On average, calling intval() is two and a half times slower, and the d...
Java: Detect duplicates in ArrayList?
How could I go about detecting (returning true/false) whether an ArrayList contains more than one of the same element in Java?
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你不得不知道的6个用好大数据的秘诀 - 资讯 - 清泛网 - 专注C/C++及内核技术
...o;往往并不能代表整个‘森林’。”Luzzi说，“如果使用了错误的数据，得出的结论往往也是错的。”
数据选择上的错误会影响人们解决问题的过程，也会影响人们如何看待这些数据和结果。错误的数据选择可能影响到公...
Is there a performance difference between a for loop and a for-each loop?
...e
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When you see the colon (:), read it as
“in.” Thus, the loop above reads as
“for each...
What is this 'Lambda' everyone keeps speaking of?
...mportant part of the loop, and abstract away the rest:
for (var i=0; i<array.length; i++) {
// do what something useful with array[i]
}
by using the forEach of array objects, becomes:
array.forEach(function (element, index) {
// do something useful with element
// element is the equ...
How can I explicitly free memory in Python?
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I need to load and process several numpy arrays of 25GB in a system with 32GB memory. Using del my_array followed by gc.collect() after processing the array is the only way the memory is actually released and my process survives to load the next array.
...