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Tricks to manage the available memory in an R session

... I make aggressive use of the subset parameter with selection of only the required variables when passing dataframes to the data= argument of regression functions. It does result in some errors if I forget to add variables to both the formula and the select= vector, but it sti...
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How to get the max of two values in MySQL?

... Use GREATEST() E.g.: SELECT GREATEST(2,1); Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7) s...
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Difference between Python's Generators and Iterators

...ry generator is an iterator, but not vice versa. A generator is built by calling a function that has one or more yield expressions (yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph's definition of an iterator. You may want to use a custom iterator, ra...
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How to do joins in LINQ on multiple fields in single join

...d2}, (x, y) => x); While the last argument (x, y) => x is what you select (in the above case we select x). share | improve this answer | follow | ...
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Using property() on classmethods

... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter: ...
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Loop through all the resources in a .resx file

...et.OfType<DictionaryEntry>(). Using LINQ allows you, for example, to select resources based on their index (int) instead of key (string): ResourceSet resourceSet = Resources.ResourceManager.GetResourceSet(CultureInfo.CurrentUICulture, true, true); foreach (var entry in resourceSet.OfType<D...
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How to avoid having class data shared among instances?

...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other. – Matt Moriarity Nov 5 '09 at 14:04 ...
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How to import other Python files?

... importlib was added to Python 3 to programmatically import a module. It is just a wrapper around __import__, see the docs. import importlib moduleName = input('Enter module name:') importlib.import_module(moduleName) Note: the .py extension should be removed from mod...
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Where can I find the TypeScript version installed in Visual Studio?

...2013 -> Visual Studio Tools A windows is open with a list of tool. Select Developer Command Prompt for VS2013 In the opened Console write: tsc -v You get the version: See Image [UPDATE] If you update your Visual Studio to a new version of Typescript as 1.0.x you don't see the last ver...
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Inheritance and Overriding __init__ in python

... The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes. It looks like this nowadays: class FileInfo(dict): """store file metadata""" def __init__(self, filename=None): super(FileInfo,...