大约有 49,000 项符合查询结果（耗时：0.0441秒） [XML]
Count number of rows within each group
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I don't know but this could be useful as well... df %>% group_by(group, variable) %>% mutate(count = n())
– Manoj Kumar
Dec 14 '16 at 17:57
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Determine if string is in list in JavaScript
...}
// Result:
0
1
2
blah // Extra member iterated over!
Your code may work now, but the moment someone in the future adds a third-party JavaScript library or plugin that isn't zealously guarding against inherited keys, everything can break.
The old way to avoid that breakage is, during enumeration, ...
Total width of element (including padding and border) in jQuery
...t the time where not adequate by themselves to calculate the whole width.
Now, as J-P correctly states, jQuery has the functions outerWidth and outerHeight which include the border and padding by default, and also the margin if the first argument of the function is true
[Original answer]
The w...
What is Node.js' Connect, Express and “middleware”?
Despite knowing JavaScript quite well, I'm confused what exactly these three projects in Node.js ecosystem do. Is it something like Rails' Rack? Can someone please explain?
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Fancybox doesn't work with jQuery v1.9.0 [ f.browser is undefined / Cannot read property 'msie' ]
...s patched.
UPDATE (Jan 16, 2013): Fancybox v2.1.4 has been released and now it works fine with jQuery v1.9.0.
For fancybox v1.3.4- you still need to rollback to jQuery v1.8.3 or apply the migration script as pointed out by @Manu's answer.
UPDATE (Jan 17, 2013): Workaround for users of Fancyb...
Git: Correct way to change Active Branch in a bare repository?
...zarre. Just goes to show how hard it is to find something when you don't know exactly what you're looking for.
– kbro
Jul 22 '10 at 8:51
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Relation between CommonJS, AMD and RequireJS?
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FYI Browserify will now let you use CommonJS in the browser.
– Eruant
Jan 30 '14 at 12:03
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How does cookie based authentication work?
...y won't see your users' actual passwords.
Step 3: Client > User login
Now your user logs in. He/she provides their username/password and again, this is posted as a HTTP request to the server.
Step 4: Server > Validating login
The server looks up the username in the database, hashes the sup...
Replace a newline in TSQL
...e characters from the endpoints of the string, not from the 'body'.
Okay, now that the disclaimer is updated, here's the code.
-- =============================================
-- Description: TRIMs a string 'for real' - removes standard whitespace from ends,
-- and replaces ASCII-char's 9-13, whic...
Best JavaScript compressor [closed]
...tter than YUI on all scripts I tested it on, and it's safer than Closure (knows to deal with "eval" or "with").
Other than whitespace removal, UglifyJS also does the following:
changes local variable names (usually to single characters)
joins consecutive var declarations
avoids inserting any unne...