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How to test an Internet connection with bash?
How can an internet connection be tested without pinging some website?
I mean, what if there is a connection but the site is down? Is there a check for a connection with the world?
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How do I do an OR filter in a Django query?
...ould this be done programmatically? So, for example be able to have for f in filters: Item.objects.filter(Q(creator=f1) | Q(creator=f2) | ...)
– Alexis
Aug 10 '12 at 20:05
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What is the purpose of flush() in Java streams?
In Java, flush() method is used in streams. But I don't understand what are all the purpose of using this method?
6 Answe...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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What does .SD stand for in data.table in R
.SD looks useful but I do not really know what I am doing with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it?
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How to show first commit by 'git log'?
...0 HEAD
(from tiho's comment. As Chris Johnsen notices, --max-parents was introduced after this answer was posted.)
Explanation
Technically, there may be more than one root commit. This happens when multiple previously independent histories are merged together. It is common when a project is inte...
OS X Framework Library not loaded: 'Image not found'
I am trying to create a basic OS X Framework, right now I just have a test framework created: TestMacFramework.framework and I'm trying to import it into a brand new OS X Application project.
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How to use DISTINCT and ORDER BY in same SELECT statement?
After executing the following statement:
12 Answers
12
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Creating a copy of an object in C# [duplicate]
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There is no built-in way. You can have MyClass implement the IClonable interface (but it is sort of deprecated) or just write your own Copy/Clone method. In either case you will have to write some code.
For big objects you could consider Ser...
How can I click a button behind a transparent UIView?
...ne sub view. the subview takes up the center of the screen with 100 px margins on all sides. We then add a bunch of little stuff to click on inside that subview. We are only using the subview to take advantage of the new frame ( x=0, y=0 inside the subview is actually 100,100 in the parent view).
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