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In where shall I use isset() and !empty()
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edited Jul 22 '19 at 11:16
simhumileco
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Encoding an image file with base64
...ion. I assume you are doing something along the lines of:
import base64
with open("yourfile.ext", "rb") as image_file:
encoded_string = base64.b64encode(image_file.read())
You have to open the file first of course, and read its contents - you cannot simply pass the path to the encode functio...
Why is pow(a, d, n) so much faster than a**d % n?
I was trying to implement a Miller-Rabin primality test , and was puzzled why it was taking so long (> 20 seconds) for midsize numbers (~7 digits). I eventually found the following line of code to be the source of the problem:
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define() vs. const
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As of PHP 5.3 there are two ways to define constants: Either using the const keyword or using the define() function:
const FOO = 'BAR';
define('FOO', 'BAR');
The fundamental difference between those two ways is that const defines constants at compile time, whereas define defin...
C++代码执行安装包静默安装 - C/C++ - 清泛网 - 专注C/C++及内核技术
...装。1.-----------------------CreateProcess---------------------- PROCESS_INFORMATIO...需求：安装包下载完成后，创建一个子进程自动安装。
1.-----------------------CreateProcess----------------------
PROCESS_INFORMATION pi;
STARTUPINFO si;
memset( &si, ...
Transposing a 2D-array in JavaScript
...lback is invoked only for indexes of the array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values.
callback is invoked with three arguments: the value of the element, the index of the element, and the Array object being tra...
Migration: Cannot add foreign key constraint
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Add it in two steps, and it's good to make it unsigned too:
public function up()
{
Schema::create('priorities', function($table) {
$table->increments('id', true);
$table->integer('user_id')->unsigned...
How to save a PNG image server-side, from a base64 data string
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You need to extract the base64 image data from that string, decode it and then you can save it to disk, you don't need GD since it already is a png.
$data = 'data:image/png;base64,AAAFBfj42Pj4';
list($type, $data) = explode(';', $data);
list(, $data) = explode(',', $data);
$data = base...
URL rewriting with PHP
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You can essentially do this 2 ways:
The .htaccess route with mod_rewrite
Add a file called .htaccess in your root folder, and add something like this:
RewriteEngine on
RewriteRule ^/?Some-text-goes-here/([0-9]+)$ /picture.php?id=$1
This will tell Apache to enable mod_rewrite fo...
std::find，std::find_if使用小结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...、STL容器进行查找的方法。使用该函数，需 #include <algorithm>我们查找一个list中的数据，通常...STL的find，find_if函数提供了一种对数组、STL容器进行查找的方法。使用该函数，需添加
#include <algorithm>
我们查找一个vector中的数据...