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Subset of rows containing NA (missing) values in a chosen column of a data frame
...ated. THe point is to use is.na, I wrongly interpreted you wanted to check all variables.
– Joris Meys
Nov 2 '11 at 21:34
3
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In PHP what does it mean by a function being binary-safe?
...ing is more specific, referring only to what Michael gives as an example.
All strings in PHP have a length associated, which are the number of bytes that compose it. When a function manipulates a string, it can either:
Rely on that length meta-data.
Rely on the string being null-terminated, i.e.,...
How can I combine flexbox and vertical scroll in a full-height app?
...lapping effects, but you shouldn't rely on that unless you want to accidentally confuse yourself later. (Default is flex:0 1 auto, so they start at their auto height and can shrink but not grow, but they're also overflow:visible by default, which triggers their default min-height:auto to prevent the...
Homebrew’s `git` not using completion
When using OSX’s git, after I modify a file I can simply do git commit <tab> , and that’ll auto complete the file’s name to the one that was modified. However, if I install a newer version of git from homebrew and I use it, that feature no longer works (meaning I press <tab> and...
C++代码执行安装包静默安装 - C/C++ - 清泛网 - 专注C/C++及内核技术
... szCmdline = _T("/NCRC /S /D=\"");
szCmdline.Append( DEFAULT_INSTALL_PATH );
szCmdline.Append( _T("\"") );
CreateProcess( szSetupPath, szCmdline.GetBuffer(), NULL, FALSE, NULL, NULL, NULL, szWorking, &si, &pi );
WaitForSingleObject( m_hCreatePackage, INFINITE ); // 这种方...
Paperclip::Errors::MissingRequiredValidatorError with Rails 4
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Starting with Paperclip version 4.0, all attachments are required to include a content_type validation, a file_name validation, or to explicitly state that they're not going to have either.
Paperclip raises Paperclip::Errors::MissingRequiredValidatorError erro...
Difference Between ViewData and TempData?
I know what ViewData is and use it all the time, but in ASP.NET Preview 5 they introduced something new called TempData.
6...
Best practices for reducing Garbage Collector activity in Javascript
I have a fairly complex Javascript app, which has a main loop that is called 60 times per second. There seems to be a lot of garbage collection going on (based on the 'sawtooth' output from the Memory timeline in the Chrome dev tools) - and this often impacts the performance of the application.
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How to position a DIV in a specific coordinates?
... edited Apr 15 '16 at 14:16
allegutta
5,39777 gold badges3131 silver badges4949 bronze badges
answered Jul 23 '11 at 20:01
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How do you create a remote Git branch?
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First, you create your branch locally:
git checkout -b <branch-name> # Create a new branch and check it out
The remote branch is automatically created when you push it to the remote server. So when you feel ready for it, you can just do:
git push &...