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Why can't I use switch statement on a String?
...t compile time. At runtime, while the O(1) performance of tableswitch generally appears better than the O(log(n)) performance of lookupswitch, it requires some analysis to determine whether the table is dense enough to justify the space–time tradeoff. Bill Venners wrote a great article that covers...
Determine the data types of a data frame's columns
...ation as a vector (i.e. you don't need it to do something else programmatically later), just use str(foo).
In both cases foo would be replaced with the name of your data frame.
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Xcode 5: Code signing entitlement errors
...both rows, however, I saw the "Any iOS SDK" subrows for each configuration all set to None, although the Debug/Release rows did list the proper profile/signing identity. Archiving in this state still gave me the error, until I explicitly set all the "Any iOS SDK" rows to their proper values.
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Shell one liner to prepend to a file
...t it sorta worked but weird things could happen, or it just didn't work at all, so it was furiously downvoted for a time. Such fun.
The solution exploits the exact implementation of file descriptors on your system and, because implementation varies significantly between nixes, it's success is enti...
CSS/HTML: What is the correct way to make text italic?
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Case 2 does not correspond to what HTML5 drafts actually say – which is obscure and varies by version, but no version suggests using i for book, song, album, or movie names (which would, debatably, be candidates for using cite).
– Jukka K. Korpela
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Firing events on CSS class changes in jQuery
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What's the deal with triggering the event which then calls a function? Why not call the function directly, instead of triggering it?
– RamboNo5
Dec 23 '09 at 1:11
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What is the difference between a var and val definition in Scala?
... can, then, go the other direction. If val is that better, why have var at all? Well, some languages did take that route, but there are situations in which mutability improves performance, a lot.
For example, take an immutable Queue. When you either enqueue or dequeue things in it, you get a new Qu...
Action bar navigation modes are deprecated in Android L
...king a look at the API diff report for the Android "L" preview, I see that all methods related to navigation modes in the ActionBar class (such as setNavigationMode() , addTab() , selectTab() , &c). are now deprecated.
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How many database indexes is too many?
...oject with a rather large Oracle database (although my question applies equally well to other databases). We have a web interface which allows users to search on almost any possible combination of fields.
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How to delete a whole folder and content?
...delete the DCIM folder because it is a system folder. As you delete it manually on phone it will delete the contents of that folder, but not the DCIM folder. You can delete its contents by using the method below:
Updated as per comments
File dir = new File(Environment.getExternalStorageDirectory()...