大约有 43,000 项符合查询结果（耗时：0.0606秒） [XML]
Convert data.frame column to a vector?
... The reminder of drop=FALSE is useful - this helps me in cases where I may select N columns from a data.frame, in those cases where N=1.
– Iterator
Aug 15 '11 at 20:42
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In c# what does 'where T : class' mean?
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Voted down, it must not be selected as answer.
– Jonathan
Aug 22 at 17:30
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Using JQuery to check if no radio button in a group has been checked
... answer worked for me reliably to check whether a radio button group had a selected value. Best answer in the thread.
– Andy Cook
Apr 29 '13 at 19:21
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How to reset Android Studio
...e list of recent projects. Now right click the item you want to remove and select Remove from list (repeat for all items to remove).
– free3dom
Nov 19 '14 at 7:24
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Where does PostgreSQL store the database?
...e tablespaces, which might not be in that data directory, use this query.
SELECT * FROM pg_tablespace;
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Do I need Content-Type: application/octet-stream for file download?
...inline some would always use it, while others would use it if the user had selected "save link as" but not if they'd selected "save" while viewing (or at least IE used to be like that, it may have changed some years ago).
sh...
Calculate the median of a billion numbers
...r sending data over a network to be faster than sorting it (let alone just selecting the median) it needs to be a pretty damn fast network. Might be a better prospect if the network can be presumed to be instantaneous, for example if you have 100 cores with equal access to RAM containing the data.
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Count immediate child div elements using jQuery
...est to see the speed difference and the children() method beaten the child selector (#foo > div) approach by at least 60% in Chrome (canary build v15) 20-30% in Firefox (v4).
By the way, needless to say, these two approaches produce same results (in this case, 1000).
[Update] I've updated the t...
Efficiently updating database using SQLAlchemy ORM
...ill basically run the same SQL statement as the previous snippet, but also select the changed rows and expire any stale data in the session. If you know you aren't using any session data after the update you could also add synchronize_session=False to the update statement and get rid of that select....
UITextField auto-capitalization type - iPhone App
...nspector of the interface builder when you have the appropriate text field selected:
"Capitalization" is the first option in this group, just passed picking the minimum font size for the text field.
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