大约有 46,000 项符合查询结果（耗时：0.0356秒） [XML]
List comprehension: Returning two (or more) items for each item
...bda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_itera...
How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...BSession.query(model.Name).distinct(model.Name.value) \
.order_by(model.Name.value)
Or just any kind of session.query().
Thanks to Nicolas Cadou for the answer! I hope it helps others who come searching here.
...
How do I find which rpm package supplies a file I'm looking for?
As an example, I am looking for a mod_files.sh file which presumably would come with the php-devel package. I guessed that yum would install the mod_files.sh file with the php-devel x86_64 5.1.6-23.2.el5_3 package, but the file appears to not to be installed on my filesystem.
...
What is the difference between HTTP_HOST and SERVER_NAME in PHP?
What is the difference between HTTP_HOST and SERVER_NAME in PHP?
10 Answers
10
...
Extracting text OpenCV
...s(cv::Mat img)
{
std::vector<cv::Rect> boundRect;
cv::Mat img_gray, img_sobel, img_threshold, element;
cvtColor(img, img_gray, CV_BGR2GRAY);
cv::Sobel(img_gray, img_sobel, CV_8U, 1, 0, 3, 1, 0, cv::BORDER_DEFAULT);
cv::threshold(img_sobel, img_threshold, 0, 255, CV_THRESH_O...
Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
CORS Access-Control-Allow-Headers wildcard being ignored?
...d-By, X-Requested-With
.htaccess Example (CORS Included):
<IfModule mod_headers.c>
Header unset Connection
Header unset Time-Zone
Header unset Keep-Alive
Header unset Access-Control-Allow-Origin
Header unset Access-Control-Allow-Headers
Header unset Access-Control-Expose-Headers
...
How to intercept click on link in UITextView?
...View shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange *NS_DEPRECATED_IOS(7_0, 10_0, "Use textView:shouldInteractWithURL:inRange:forInteractionType: instead");*
to intercept the clicks to links. And this is the best way to do it.
For ios6 and earlier a nice way to do this is to b...
Download the Android SDK components for offline install
...available
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Fetched Add-ons List successfully
Fetching URL: https://dl-ssl.google.com/android/repository/repository-7.xml
Validate XML: https://dl-ssl.google.com/android/repository/repository-7.xml
Parse XML: https...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...use a query like this: "start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * ...