大约有 3,060 项符合查询结果（耗时：0.0443秒） [XML]
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
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The tidyr package from the tidyverse has an excellent function that does this.
Assuming your variables are named v1, v2 and v3, left to right, and you data frame is named dat:
dat %>%
spread(key = v2,
value = v3)
Ta da!
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Is modern C++ becoming more prevalent? [closed]
... always maintaining backwards compatibility with DOS. (See Raymond Chen's excellent blog for the often painful lengths they went to...)
– j_random_hacker
Feb 13 '09 at 3:27
2
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ng-options with simple array init
...ng-selected does not need the handlebars since it is an angular directive. Excellent solution.
– Kasey Speakman
Dec 9 '14 at 21:03
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Get the full URL in PHP
...im values to filename, i.e.
basename($url) ???? myfile.php
//excellent solution to find origin
$debug_files = debug_backtrace();
$caller_file = count($debug_files) ? $debug_files[count($debug_files) - 1]['file'] : __FILE__;
Notice ! ! !
hashtag # parts were manually used in th...
Case-INsensitive Dictionary with string key-type in C#
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Excellent for deserialized from JSON. Saved me a big headache.
– Hugo Scott-Slade
Aug 21 at 10:54
ad...
How do I sort an observable collection?
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Excellent solution! For the ones inheriting from ObservableCollection<T>, it's possible to use the protected MoveItem() method instead of using the RemoveAt and Insert methods. See also: referencesource.microsoft.com/#s...
How do browser cookie domains work?
...isunderstanding. Sorry for thread necromancy but wanted to make sure this excellent answer was 100% accurate for future confused newbies like me :)
– errah
Apr 9 '14 at 2:43
7
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Prevent scrolling of parent element when inner element scroll position reaches top/bottom? [duplicat
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Excellent, comprehensive and easy to understand answer.
– David Tuite
Oct 21 '13 at 11:57
2
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What is “point free” style (in Functional Programming)?
...ually the one that looks pointier (more periods). This annoyance makes an excellent mnemonic. (The book Real World Haskell comments on this.)
– Dan
Jul 8 '10 at 20:06
3
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How would one write object-oriented code in C? [closed]
...ve that besides being useful in its own right, implementing OOP in C is an excellent way to learn OOP and understand its inner workings. Experience of many programmers has shown that to use a technique efficiently and confidently, a programmer must understand how the underlying concepts are ultimate...