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When do items in HTML5 local storage expire?
For how long is data stored in localStorage (as part of DOM Storage in HTML5) available? Can I set an expiration time for the data which I put into local storage?
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Windows Explorer “Command Prompt Here” [closed]
I frequently find myself with a folder open in Windows, wishing to have a command prompt open with the same working directory.
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Easy way to write contents of a Java InputStream to an OutputStream
I was surprised to find today that I couldn't track down any simple way to write the contents of an InputStream to an OutputStream in Java. Obviously, the byte buffer code isn't difficult to write, but I suspect I'm just missing something which would make my life easier (and the code clearer).
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Swift Beta performance: sorting arrays
I was implementing an algorithm in Swift Beta and noticed that the performance was very poor. After digging deeper I realized that one of the bottlenecks was something as simple as sorting arrays. The relevant part is here:
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Why does sun.misc.Unsafe exist, and how can it be used in the real world?
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examples
VM "intrinsification." ie CAS (Compare-And-Swap) used in Lock-Free Hash Tables
eg:sun.misc.Unsafe.compareAndSwapInt
it can make real JNI calls into native code that contains special instructions for CAS
read more about CAS here ...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
Ive got a bunch of rectangular objects which I need to pack into the smallest space possible (the dimensions of this space should be powers of two).
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Setting UIButton image results in blue button in iOS 7
On iOS 6 SDK I wrote the following lines of code to display an image inside a button:
15 Answers
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How do I convert this list of dictionaries to a csv file?
I have a list of dictionaries that looks something like this:
7 Answers
7
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Convert one date format into another in PHP
Is there a simple way to convert one date format into another date format in PHP?
15 Answers
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How to drop columns by name in a data frame
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You should use either indexing or the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operat...