大约有 47,000 项符合查询结果（耗时：0.0327秒） [XML]
How to remove an element from a list by index
...
Use del and specify the index of the element you want to delete:
>>> a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> del a[-1]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8]
Also supports slices:
>>> del a[2:4]
>...
Why does changing the sum order returns a different result?
...gnificant digits, where each addition is performed at "infinite" precision and then rounded to the nearest representable number. Here are two sums:
1/3 + 2/3 + 2/3 = (0.3333 + 0.6667) + 0.6667
= 1.000 + 0.6667 (no rounding needed!)
= 1.667 (where 1.6667 is rounded to...
Common CSS Media Queries Break Points [duplicate]
...ular layout instead. That is, gradually narrow your desktop browser window and observe the natural breakpoints for your content. It's different for every site. As long as the design flows well at each browser width, it should work pretty reliably on any screen size (and there are lots and lots of t...
What is the difference between procedural programming and functional programming? [closed]
I've read the Wikipedia articles for both procedural programming and functional programming , but I'm still slightly confused. Could someone boil it down to the core?
...
How to shorten my conditional statements
...
Put your values into an array, and check if your item is in the array:
if ([1, 2, 3, 4].includes(test.type)) {
// Do something
}
If a browser you support doesn't have the Array#includes method, you can use this polyfill.
Short explanation of the ...
Is there a MySQL option/feature to track history of changes to records?
...QL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
...
HSL to RGB color conversion
...(which he attributes to a now defunct mjijackson.com, but is archived here and the original author has a gist - thanks to user2441511).
The code is re-posted below:
HSL to RGB:
/**
* Converts an HSL color value to RGB. Conversion formula
* adapted from http://en.wikipedia.org/wiki/HSL_color_sp...
How to create a self-signed certificate with OpenSSL
...
You can do that in one command:
openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365
You can also add -nodes (short for no DES) if you don't want to protect your private key with a passphrase. Otherwise it will prompt you for "...
How to check if a number is a power of 2
...eturn (x != 0) && ((x & (x - 1)) == 0);
}
Explanation
First and foremost the bitwise binary & operator from MSDN definition:
Binary & operators are predefined for the integral types and bool. For
integral types, & computes the logical bitwise AND of its operands.
F...
Install dependencies globally and locally using package.json
...d to do this. What you probably want to do is just put those types of command dependencies for build/test etc. in the devDependencies section of your package.json. Anytime you use something from scripts in package.json your devDependencies commands (in node_modules/.bin) act as if they are in your...