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Are list-comprehensions and functional functions faster than “for loops”?

...ike map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?. ...
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What is the meaning of “__attribute__((packed, aligned(4))) ”

...gned(1))) sSampleStruct; so the above specified gcc attribute does not allow the structure padding. so the size will be 8 bytes. If you wish to do the same for all the structures, simply we can push the alignment value to stack using #pragma #pragma pack(push, 1) //Structure 1 ...... //Stru...
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Checking images for similarity with OpenCV

...he same image was passed twice, 0% would be returned if the images were totally different. 4 Answers ...
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Is it possible to make abstract classes in Python?

...nitions of those methods: >>> Abstract() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: Can't instantiate abstract class Abstract with abstract methods foo >>> class StillAbstract(Abstract): ... pass ... >>> StillAbstr...
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How to get all Errors from ASP.Net MVC modelState?

I want to get all the error messages out of the modelState without knowing the key values. Looping through to grab all the error messages that the ModelState contains. ...
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add column to mysql table if it does not exist

... OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
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java get file size efficiently

...97.044 URL sum: 95534, per Iteration: 382.136 File must be caching the calls to the filesystem, while channels and URL have some overhead. Code: import java.io.*; import java.net.*; import java.util.*; public enum FileSizeBench { LENGTH { @Override public long getResult() ...
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What's the difference between utf8_general_ci and utf8_unicode_ci?

...languages or characters. On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers. Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci utf8mb4_unicode_ci, which uses the Unicode r...
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Sending an HTTP POST request on iOS

...format. NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES]; You need to send the actual length of your data. Calculate the length of the post string. NSString *postLength = [NSString stringWithFormat:@"%d",[postData length]]; 3. Create a Urlrequest wi...
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event.returnValue is deprecated. Please use the standard event.preventDefault() instead

... I doubt this anyone will break this anytime soon if it means causing all pages using JQuery < 1.11 to break. – Backpackcoder Nov 27 '13 at 2:25 26 ...