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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
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Android adb “Unable to open sync connection!”
...e-enabling it has worked so far. Hopefully it keeps working! These fixes really seem like silly hacks.. I'm not sure what the underlying problem is.
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Throw away local commits in Git
...commits ahead of the origin, and not in a good state. I want to get rid of all these commits and start over again.
19 Answe...
Is D a credible alternative to Java and C++? [closed]
...of a programming language for real-world software development is only partially related to the quality of the language itself. As a pure language, D arguably has many advantages over C++ and Java. At the very least it is a credible alternative as a pure language, all other things being equal.
How...
How to disable text selection highlighting
... a CSS standard way to disable the highlighting effect if the user accidentally selects the text?
48 Answers
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Are non-synchronised static methods thread safe if they don't modify static class variables?
... case) are also thread-safe because once created they can't be changed and all threads see the same value. On the other hand if the method was accepting (mutable) Date you could have had a problem. Two threads can simultaneously modify that same object instance, causing race conditions and visibilit...
Best way to load module/class from lib folder in Rails 3?
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# Autoload lib/ folder including all subdirectories
config.autoload_paths += Dir["#{config.root}/lib/**/"]
Source: Rails 3 Quicktip: Autoload lib directory including all subdirectories, avoid lazy loading
Please mind that files contained in the lib folder...
the item you requested is not available for purchase
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Make sure to upload the signed APK to developer console.
Make sure to install the signed APK on your device not launch the app in the debugger.
Make sure to create a test account in your developer console.
Setup you testing account
Make sure to sign in your device with your test account.
In a cas...
How do I prevent the padding property from changing width or height in CSS?
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This is pure magic! - It fixes the box model we all know and hate! i.e. makes it work the way intuition suggests it should - rather than the specs - but as far as I know doesn't break any specs either :D This article clarifies it well... stackoverflow.com/questions/779434/...
Overriding a Rails default_scope
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Short answer: Do not use default_scope unless you really have to. You'll probably be better off with named scopes. With that said, you can use with_exclusive_scope to override the default scope if you need to.
Have a look at this question for more details.
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