大约有 19,606 项符合查询结果（耗时：0.0354秒） [XML]
Numbering rows within groups in a data frame
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For making this r-faq question more complete, a base R alternative with sequence and rle:
df$num <- sequence(rle(df$cat)$lengths)
which gives the intended result:
> df
cat val num
4 aaa 0.05638315 1
2 aaa 0.25767250 2
1 aaa 0.30776611 3
5 aaa...
How to get a variable value if variable name is stored as string?
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Based on the answer: https://unix.stackexchange.com/a/111627
###############################################################################
# Summary: Returns the value of a variable given it's name as a string.
# Required ...
Choosing between std::map and std::unordered_map [duplicate]
... std::unorderded_map); if you want sorted sequential access, use something based on a vector.
Also, std::map is a balanced tree; and you have to traverse it, or re-balance it, incredibly often. These are cache-killer and cache-apocalypse operations respectively... so just say NO to std::map.
You ...
Allowing Untrusted SSL Certificates with HttpClient
... only to calls to that URI. You can then set properties and handle events based on that subset.
– oatsoda
Feb 16 '17 at 16:07
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Composer install error - requires ext_curl when it's actually enabled
... The question's author seems to be running Windows. Windows is not based on Debian.
– huertanix
May 14 '15 at 16:46
3
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Is there anything like inotify on Windows?
...dFirstChangeNotification. I started writing a Windows event watcher in Go, based heavily on Jeffery Richter's examples. From the bit of testing I did, it is rock solid, and misses nothing, similar to fsevents in OS X. Gist is here: gist.github.com/pkrnjevic/7219861
– Peter Krnj...
Angular JS break ForEach
...gularJS you can iterate with $.each - which allows breaking and continuing based on boolean return value expression.
JSFiddle:
http://jsfiddle.net/JEcD2/1/
Javascript:
var array = ['foo', 'bar', 'yay'];
$.each(array, function(index, element){
if (element === 'foo') {
return true; // ...
How can I get an http response body as a string in Java?
...any cases as the method uses the system default text encoding which varies based on OS and user settings.
– McDowell
Apr 24 '11 at 10:20
1
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How to vertically align a html radio button to it's label?
...l, then I may need to set margin-top to a value less than -1px (like -3px) based on how much padding I was using on that label. (I like to give my radio box labels a hover color and rounded border effect to make them look cooler.)
– Volomike
May 9 '16 at 0:26
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Best way to list files in Java, sorted by Date Modified?
...re first. My solution was to call File.listFiles and just resort the list based on File.lastModified, but I was wondering if there was a better way.
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