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Reason to Pass a Pointer by Reference in C++?
...hat the user of that class could get a pointer to the internal data buffer and read/write to it, but it cannot – for example – free that buffer using delete or rebind that pointer to some other place in memory? Or did I get it wrong?
– BarbaraKwarc
Aug 4 '1...
Split comma-separated strings in a column into separate rows
... use separate_rows:
separate_rows(v, director, sep = ",")
You can use the convert = TRUE parameter to automatically convert numbers into numeric columns.
4) with base R:
# if 'director' is a character-column:
stack(setNames(strsplit(df$director,','), df$AB))
# if 'director' is a factor-column:
sta...
How are Anonymous inner classes used in Java?
...ut actually making a separate class.
I only use this technique for "quick and dirty" tasks where making an entire class feels unnecessary. Having multiple anonymous inner classes that do exactly the same thing should be refactored to an actual class, be it an inner class or a separate class.
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How to split/partition a dataset into training and test datasets for, e.g., cross validation?
What is a good way to split a NumPy array randomly into training and testing/validation dataset? Something similar to the cvpartition or crossvalind functions in Matlab.
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Easy way of running the same junit test over and over?
...est as a parametrized test (annotate with an @RunWith(Parameterized.class) and add a method to provide 10 empty parameters). That way the framework will run the test 10 times.
This test would need to be the only test in the class, or better put all test methods should need to be run 10 times in the...
Java: Get last element after split
I am using the String split method and I want to have the last element.
The size of the Array can change.
12 Answers
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Create a GUID in Java
...
Have a look at the UUID class bundled with Java 5 and later.
For example:
If you want a random UUID you can use the randomUUID method.
If you want a UUID initialized to a specific value you can use the UUID constructor or the fromString method.
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Singleton with Arguments in Java
I was reading the Singleton article on Wikipedia and I came across this example:
20 Answers
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gcc warning" 'will be initialized after'
...
@Eloff In some cases (not recommendable), b and a initialisation might depend on each other. A naive user might try to alter the initialisation order to get some effect and the Warning would make it clear that it doesn't work.
– Gorpik
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How to create your own library for Android development to be used in every program you write?
...he new module
folder, make sure it's displaying the Android
view.
Convert an app module to a library module
If you have an existing app module with all the code you want to
reuse, you can turn it into a library module as follows:
Open the module-level build.gradle file.
Del...