大约有 40,000 项符合查询结果（耗时：0.0580秒） [XML]
What is the advantage of GCC's __builtin_expect in if else statements?
...
I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
What is the difference between .*? and .* regular expressions?
...nsider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * will match nothing, but then will try to match extra characters until it matches 1, eventually matching 101...
Running unittest with typical test directory structure
...on -m unittest test.test_antigravity.GravityTestCase.test_method
Running all tests:
You can also use test discovery which will discover and run all the tests for you, they must be modules or packages named test*.py (can be changed with the -p, --pattern flag):
$ cd new_project
$ python -m unitte...
How to check a string for specific characters?
...r other characters.
... or
pattern = re.compile(r'\d\$,')
if pattern.findall(s):
print('Found')
else
print('Not found')
... or
chars = set('0123456789$,')
if any((c in chars) for c in s):
print('Found')
else:
print('Not Found')
[Edit: added the '$' in s answers]
...
Convert json data to a html table [closed]
...
Thanks all for your replies. I wrote one myself. Please note that this uses jQuery.
Code snippet:
var myList = [
{ "name": "abc", "age": 50 },
{ "age": "25", "hobby": "swimming" },
{ "name": "xyz", "hobby": "programmin...
warning about too many open figures
...the other axes untouched.
plt.clf() clears the entire current figure with all its axes, but leaves the window opened, such that it may be reused for other plots.
plt.close() closes a window, which will be the current window, if not specified otherwise. plt.close('all') will close all open figures....
node.js global variables?
...
Globals are generally to be avoided, but if you really want to use them. The 3 statements below are all equivalent and will assign a var to the global scope: GLOBAL._ = require('underscore'); global._ = require('underscore'); _ = require('und...
In Python, how do I determine if an object is iterable?
...e a method like isiterable ? The only solution I have found so far is to call
21 Answers
...
How to load all modules in a folder?
...
List all python (.py) files in the current folder and put them as __all__ variable in __init__.py
from os.path import dirname, basename, isfile, join
import glob
modules = glob.glob(join(dirname(__file__), "*.py"))
__all__ = [ ba...
How do I perform the SQL Join equivalent in MongoDB?
...rect. The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <...