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Listing only directories in UNIX
... doesn't have such option).
Also, can this be done with a single line command?
20 Answers
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Mean per group in a data.frame [duplicate]
I have a data.frame and I need to calculate the mean per group (i.e. per Month , below).
8 Answers
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Which is more efficient, a for-each loop, or an iterator?
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If you are just wandering over the collection to read all of the values, then there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the ...
What's the best way to build a string of delimited items in Java?
...,char)
Java 8:
Java 8 provides joining out of the box via StringJoiner and String.join(). The snippets below show how you can use them:
StringJoiner
StringJoiner joiner = new StringJoiner(",");
joiner.add("01").add("02").add("03");
String joinedString = joiner.toString(); // "01,02,03"
Str...
How do you add a timer to a C# console application
... nice, however in order to simulate some time passing we need to run a command that takes some time and that's very clear in second example.
However, the style of using a for loop to do some functionality forever takes a lot of device resources and instead we can use the Garbage Collector to do som...
Disable, but not uninstall Resharper 4.x onwards
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You can disable ReSharper 4 and lower using the Visual Studio Add-In Manager (remove the check from check box on the left).
In ReSharper 5 and above (tested up to version 7.0.1), this is how you can suspend ReSharper from the Tools > Options > Re...
How to convert int[] to Integer[] in Java?
I'm new to Java and very confused.
13 Answers
13
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How to merge YAML arrays?
I would like to merge arrays in YAML, and load them via ruby -
5 Answers
5
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Replace multiple characters in a C# string
...\n]{2}/\n/g
s/ at the beginning means a search
The characters between [ and ] are the characters to search for (in any order)
The second / delimits the search-for text and the replace text
In English, this reads:
"Search for ; or , or \t or \r or (space) or exactly two sequential \n and repla...
Method Syntax in Objective-C
...kerView (slot machine UI on the iPhone) is being returned. From my understanding, the Method is called ' pickerView ', and returns an NSInteger.
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