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LINQ - Full Outer Join

... I don't know if this covers all cases, logically it seems correct. The idea is to take a left outer join and right outer join then take the union of the results. var firstNames = new[] { new { ID = 1, Name = "John" }, new { ID = 2, Name = "Sue"...
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Local variables in nested functions

...ints to the local variable cage in the get_petters function. When you actually call the function, that closure is then used to look at the value of cage in the surrounding scope at the time you call the function. Here lies the problem. By the time you call your functions, the get_petters function i...
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How to set target hosts in Fabric file

... @MikhailKorobov: When I followed your link, I saw "Welcome to nginx!". All the requests to code.fabfile.org domain have responses like that. – Tadeck Apr 4 '12 at 19:40 ...
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How can I generate a unique ID in Python? [duplicate]

...in newer versions, but most people probably don't have that yet, so I generally avoid this module. Caused me major headaches with listen sockets... – Glenn Maynard Jul 31 '09 at 3:14 ...
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How to delete migration files in Rails 3

... I usually: Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete. Delete the migration file manually. If there are pending migrations (i.e., the migration I removed was not the...
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Calculating a directory's size using Python?

... This walks all sub-directories; summing file sizes: import os def get_size(start_path = '.'): total_size = 0 for dirpath, dirnames, filenames in os.walk(start_path): for f in filenames: fp = os.path.join(di...
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Why do we need C Unions?

... Unions are often used to convert between the binary representations of integers and floats: union { int i; float f; } u; // Convert floating-point bits to integer: u.f = 3.14159f; printf("As integer: %08x\n", u.i); Although this ...
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What is %2C in a URL?

I'm trying to understand the structure of a URL, and I'm seeing a lot of %2C . I'm guessing this is a result of some encoding. What does that stand for? ...
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how do you filter pandas dataframes by multiple columns

...r function using query in pandas. Here you have filtering of df results by all the kwargs parameters. Dont' forgot to add some validators(kwargs filtering) to get filter function for your own df. def filter(df, **kwargs): query_list = [] for key in kwargs.keys(): query_list.append(f...
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I want to get the type of a variable at runtime

...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here. Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple: val x = 5 x.ge...