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Drop unused factor levels in a subsetted data frame
...he factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
14 Answers
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Read text file into string array (and write)
...starting with a language removing the need initially to access a database. Does one exist in Golang?
e.g.
5 Answers
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Using Django time/date widgets in custom form
...r time, and the many hacks required, probably ought to caution you against doing this at all. It's relying on undocumented internal implementation details of the admin, is likely to break again in future versions of Django, and is no easier to implement than just finding another JS calendar widget a...
XML parsing of a variable string in JavaScript
...
Update: For a more correct answer see Tim Down's answer.
Internet Explorer and, for example, Mozilla-based browsers expose different objects for XML parsing, so it's wise to use a JavaScript framework like jQuery to handle the cross-browsers differences.
A really b...
Alternatives to dispatch_get_current_queue() for completion blocks in iOS 6?
...letionHandler
{
dispatch_async(self.workQueue, ^{
[self doSomeWork];
dispatch_async(self.callbackQueue, completionHandler);
}
}
share
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improve this answer
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How to get root access on Android emulator?
...o 2.3.3), and I tried many methods for getting root in Android emulator. I don't use any Android device and test everything on emulator(AVD).
...
How do I install ASP.NET MVC 5 in Visual Studio 2012?
...sers of Visual Studio 2012 and Visual Studio 2012 Express for Web.
You can download and start using these features now.
The download link is to a Web Platform Installer that will allow you to start a new MVC5 project from VS2012.
...
T-SQL split string
...
This doesn't work for select * from dbo.splitstring('')
– Pasi Savolainen
Sep 18 '17 at 13:17
2
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How to install packages offline?
What's the best way to download a python package and it's dependencies from pypi for offline installation on another machine? Is there any easy way to do this with pip or easy_install? I'm trying to install the requests library on a FreeBSD box that is not connected to the internet.
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How to check if a python module exists without importing it
...le('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
imp.find_module('eggs', spam.__path__) # __path__ is already a list
found = T...