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How to find the JVM version from a program?

... That JMX call returns the equivalent of "java.vm.version", not "java.version". These are usually (but not necessarily) the same. – Alex Miller Jun 21 '13 at 15:54 ...
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namedtuple and default values for optional keyword arguments

...lds) >>> Node() Node(val=None, left=None, right=None) Order In all versions of Python, if you set fewer default values than exist in the namedtuple, the defaults are applied to the rightmost parameters. This allows you to keep some arguments as required arguments. >>> Node.__ne...
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How to check if the string is empty?

... s.strip() allocates a new string, which is pure waste. Use string.isspace() – Clément Jun 22 at 15:27 add a ...
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What is the difference between join and merge in Pandas?

... pandas.merge() is the underlying function used for all merge/join behavior. DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...
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Swift Beta performance: sorting arrays

...t)) // [-1, 0, 2, 2, 5, 8, 1234] // [-1, 0, 2, 2, 5, 8, 1234] Both are called in the same program as written. var x_swift = CInt[](count: n, repeatedValue: 0) var x_c = CInt[](count: n, repeatedValue: 0) for var i = 0; i < n; ++i { x_swift[i] = CInt(random()) x_c[i] = CInt(random()) }...
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How to call a parent method from child class in javascript?

...Here's how its done: ParentClass.prototype.myMethod(); Or if you want to call it in the context of the current instance, you can do: ParentClass.prototype.myMethod.call(this) Same goes for calling a parent method from child class with arguments: ParentClass.prototype.myMethod.call(this, arg1, arg2...
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What's the difference between dynamic (C# 4) and var?

...iteLine(s.Length); and string s = "abc"; Console.WriteLine(s.Length); All that happened was that the compiler figured out that s must be a string (from the initializer). In both cases, it knows (in the IL) that s.Length means the (instance) string.Length property. dynamic is a very different b...
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Locking a file in Python

...terminate in such a way that the lock is left in place and you have to manually delete the lock before the file becomes accessible again. However, that aside, this is still a good solution. – leetNightshade Nov 8 '12 at 21:27 ...
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Get model's fields in Django

Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
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StringBuilder vs String concatenation in toString() in Java

...o builder? At the point where you're concatenating in a loop - that's usually when the compiler can't substitute StringBuilder by itself. share | improve this answer | foll...