大约有 40,000 项符合查询结果（耗时：0.0332秒） [XML]
Resetting generator object in Python
I have a generator object returned by multiple yield. Preparation to call this generator is rather time-consuming operation. That is why I want to reuse the generator several times.
...
How can I represent an 'Enum' in Python?
...y3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum # for enum34, or the stdlib version
# from aenum import...
Extracting bits with a single multiplication
.....
A multiplication is a bunch of shift-and-add operations. The key is to allow overflow to "shift away" the bits we don't need and put the ones we want in the right place.
Multiplication by 4 (00000100) would shift everything left by 2 and get you to a00b0000 . To get the b to move up we need to...
Download the Android SDK components for offline install
Is it possible to download the Android SDK components for offline install without using the SDK Manager?
The problem is I am behind a firewall which I have no control over and both sites download URLs seem to be blocked (throws a connection refused exception)
...
Can I have multiple Xcode versions installed?
Is it possible to have more than one version of Xcode installed at the same time?
12 Answers
...
How to calculate a time difference in C++
...turns the CPU time consumed by the program. So if the program is run in parallel the time returned by the function would be the accumulated of the time spent on all CPUs, rather than the time elapsed cplusplus.com/reference/ctime/clock
– Ameer Jewdaki
Aug 3 '1...
What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
Inserting multiple rows in mysql
...
When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.
Optimizing INSERT Statements
You can find more tips on how to speed up your insert statements on the link above.
...
Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0
...it Ad Tracking.
Including Limit Ad Tracking. This is what the last box is all about. So you must check the that box if you use AdMob. If you use other SDK I strongly recommend checking if they respect the guidelines as well.
Since I run only ads (Google AdMob), I checked the first (Serve ads...) a...
Force CloudFront distribution/file update
...
Good news. Amazon finally added an Invalidation Feature. See the API Reference.
This is a sample request from the API Reference:
POST /2010-08-01/distribution/[distribution ID]/invalidation HTTP/1.0
Host: cloudfront.amazonaws.com
Authorization:...