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Coding Practices which enable the compiler/optimizer to make a faster program

...act. Expect to be disappointed and to have to work very hard indeed for small performance improvements. Modern compilers for mature languages such as Fortran and C are very, very good. If you read an account of a 'trick' to get better performance out of code, bear in mind that the compiler writer...
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Regular expression to allow spaces between words

I want a regular expression that prevents symbols and only allows letters and numbers. The regex below works great, but it doesn't allow for spaces between words. ...
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Python memory leaks [closed]

... have a long-running script which, if let to run long enough, will consume all the memory on my system. 9 Answers ...
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Get notified when UITableView has finished asking for data?

...eload its data. So, when the second NSLog is fired, the table view has actually finish asking for data. I've subclassed UITableView to send methods to the delegate before and after reloadData. It works like a charm. share ...
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What is the pythonic way to avoid default parameters that are empty lists?

...he preferred way in this example is to say: if working_list is None . The caller might have used an empty list-like object with a custom append. – tzot Dec 14 '08 at 12:45 5 ...
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Rails Root directory path?

... Personally I like the newer syntax: Rails.root / 'app' / 'assets' / 'images' / 'logo.png' – Ajedi32 Feb 18 '16 at 17:13 ...
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How to manually set an authenticated user in Spring Security / SpringMVC

After a new user submits a 'New account' form, I want to manually log that user in so they don't have to login on the subsequent page. ...
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How can I use numpy.correlate to do autocorrelation?

...olution, C(t)=∑ -∞ < i < ∞ aivt+i where -∞ < t < ∞, allows for results from -∞ to ∞, but you obviously can't store an infinitely long array. So it has to be clipped, and that is where the mode comes in. There are 3 different modes: full, same, & valid: "full" mode r...
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Are there any disadvantages to always using nvarchar(MAX)?

In SQL Server 2005, are there any disadvantages to making all character fields nvarchar(MAX) rather than specifying a length explicitly, e.g. nvarchar(255)? (Apart from the obvious one that you aren't able to limit the field length at the database level) ...
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Get a random boolean in python?

... but I found that random.getrandbits(1) to be quite a lot faster. If you really want a boolean instead of a long then bool(random.getrandbits(1)) is still about twice as fast as random.choice([True, False]) Both solutions need to import random If utmost speed isn't to priority then random.choic...