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What's the fastest way to merge/join data.frames in R?
...eVersion("sqldf")
# [1] ‘0.4.6.4’
R.version.string
# R version 2.15.1 (2012-06-22)
Please note that I don't know plyr well so please do check with Hadley before relying on the plyr timings here. Also note that the data.table do include the time to convert to data.table and set the key, for far...
Should CSS always preceed Javascript?
...of worldwide desktop browser users using this version or greater as of Jan 2012)
Chrome 1 (WebKit 525) (100%)
IE 8 (75%)
Firefox 3.5 (96%)
Safari 4 (99%)
Opera 11.60 (85%)
In total, roughly 85% of desktop browsers in use today support speculative loading. Putting scripts before CSS will have a ...
lenses, fclabels, data-accessor - which library for structure access and mutation is better
...te-haskell machinery is now available via data-lens-template.
Update 6/28/2012: Other Lens Implementation Strategies
Isomorphism Lenses
There are two other lens encodings worth considering. The first gives a nice theoretical way to view a lens as a way to break a structure into the value of the f...
正则表达式 30 分钟入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...e 30 Minute Regex Tutorial。由于评论里有过长的URL,所以本页排版比较...
来园子之前写的一篇正则表达式教程，部分翻译自codeproject的The 30 Minute Regex Tutorial。
由于评论里有过长的URL,所以本页排版比较混乱,推荐你到原处...
What is std::promise?
...nd in most cases I will expect runtimes that use thread pools. Currently VS2012 does use a thread pool under the hood, and it does not violate the as-if rule. Note that there are very little guarantees that need to be fulfilled for this particular as-if.
– David Rodríguez - dr...
Are Exceptions in C++ really slow
...ortunately the report, from 2006, is already a little bit dated as of late 2012, and as far as I know there’s not anything comparable that’s newer.
Another important perspective is that the impact of use of exceptions on performance is very different from the isolated efficiency of the supporti...
Traversing text in Insert mode
...nd clicking to position the cursor (duh) just works. See http://usevim.com/2012/05/16/mouse/ for more on this.
And so...
These are what I'd call more modern (using mouse, scroll wheel, etc.) ways of navigating in vim, equally effective depending on your preference of input.
HTH
...
Hosting a Maven repository on github
...aoCore/target/mvn-repo/com/greendao-orm/greendao/1.3-SNAPSHOT/greendao-1.3-20121223.182256-3.jar (77 KB at 2936.9 KB/sec)
Uploaded: file:///Users/mike/Projects/greendao-emmby/DaoCore/target/mvn-repo/com/greendao-orm/greendao/1.3-SNAPSHOT/greendao-1.3-20121223.182256-3.pom (3 KB at 1402.3 KB/sec)
Upl...
Comparison between Mockito vs JMockit - why is Mockito voted better than JMockit? [closed]
...at a google trends comparison of all the discussed frameworks. As of 06.06.2012, JMockit doesn't even show up on the google trends graph when compared with Mockito and EasyMock. And the number of users is also important when choosing a framework.
– machinery
Ju...
What characters are allowed in an email address?
...ent to john.smith@example.com.
In addition to ASCII characters, as of 2012 you can use international characters above U+007F, encoded as UTF-8 as described in the RFC 6532 spec and explained on Wikipedia. Note that as of 2019, these standards are still marked as Proposed, but are being rolled ...